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Biosafety Issues in Hospital Settings



Federal and state regulations with a biosafety component have increased dramatically during the 1990's. The need for biological safety individuals who have hospital experience are greater today than ever before. This chapter covers many hospital-related biosafety issues, both administrative and by topic. This is a description of how biosafety functions are organized and implemented at Johns Hopkins Institutions, with observations regarding the mounting of a successful biosafety program.
Biosafety Issues in Hospital Settings
Richard W. Gilpin, Ph.D., RBP, CBSP
Federal and state regulations with a hospital biosafety component have increased
dramatically during the 1990's. The need for biological safety individuals that have
hospital experience are greater today than ever before. This chapter covers many
hospital-related biosafety issues, both administrative and by topic. This is a description
of how biosafety functions are organized and implemented at Johns Hopkins
Institutions, with observations regarding the mounting of a successful biosafety
Table of Contents
Biosafety Functions
Administrative Reporting Level
Relationship to Infection Control Programs
Advisory Functions
Line Management Functions
Service Functions
Training and Education
Record Keeping
Performance Measurement
Biosafety Related Advisory and Regulatory Organizations
Biosafety Related Administrative Programs
Airborne Isolation
Biological Air Sampling
Biological Safety Cabinets
Bloodborne Pathogens Control Program
Clean Air Benches
Cleaning and Disinfection
Construction and Renovation
Employee Health Management
Eye, Face and Body Wash
Hand Washing and Antisepsis
HEPA Filter Certification and Maintenance
Isolation Rooms
Latex Hypersensitivity
Medical Waste Containers
Needle-less IV Systems
Occupational Injury Management
Permanent HEPA Filtration
Portable HEPA Filtration
Respiratory Surveillance
Safer Sharps
Standard Precautions
Sterilization Policies
Tuberculosis Control Program
Vacuum Delivery Systems
Personal Protective Equipment
Eye Protection
Face Protection
Head and Foot Covers
Biosafety Interactions with Administrative Units
Clinical Engineering
Clinical Laboratories
Human Resources
Infection Control
Legal Affairs
Occupational Health Services
Occupational Injury Management
Materials Management (Purchasing)
Biosafety Related Hospital Committees
Hospital Safety Committee
Infection Control Committee
Protective Devices Committee
Institutional Biological Safety Committee (IBC)
Institutional Review Board
Biosafety Functions
Biosafety in hospital settings involves protection of employees from infection by
biohazardous materials that may be transmitted from patients, patient equipment, and
the hospital environment. Biohazardous materials are microorganisms or their products
that can cause disease in humans or animals. Policies and procedures are developed
to reduce employee exposures to biohazardous materials. Employee practices,
personal protective equipment, administrative controls, engineering controls, training,
and medical surveillance are components of a hospital biosafety program. While the
protection of patients is a function of infection control, inevitable overlap brings biosafety
into these issues as well.
Administrative Reporting Level
An integrated hospital reporting structure for safety operations provides the basis for
biosafety implementation. The biosafety officer should report directly to an executive,
often a physician, responsible for all employee health and safety programs including
employee health, employee assistance, occupational injury (workers’ compensation),
and occupational medicine.
The biosafety, industrial hygiene, radiation, and traditional safety (accident investigation,
fire safety, and life safety) officers should report to one individual. This individual and
the hospital epidemiologist should report to the head of medical affairs in the hospital to
provide coordination between patient and employee safety and health program
elements. Johns Hopkins Hospital has a university physician medical staff. Appointing
the executive responsible for hospital health and safety to the faculty of the university
with administrative reporting to a senior executive of the academic administration
provides coordination between hospital and university safety programs.
Some university teaching hospitals have an individual in charge of all safety divisions
reporting to the executive responsible for employee health and safety. This reduces the
number of individuals directly reporting to the executive and may ensure more
coordination between the four safety divisions (biosafety, industrial hygiene, radiation
control, and traditional safety.
Private teaching hospitals with university physicians benefit from a joint health and
safety program coordinated by one administrative unit that employs both hospital and
university staff members. Such is the case at the Johns Hopkins Hospital, which is
staffed by physicians that are Johns Hopkins University employees. The administrative
programs of the hospital and the School of Medicine are coordinated by an
administrative arrangement named Johns Hopkins Medicine. The Department of
Health, Safety and Environment has served the hospital and all schools of the university
for over two decades, resulting in a well coordinated, cost effective program. The
hospital has its own policies as does the university. Safety policies, however, are
written so that they are the same. This safety administrative arrangement uses the
name Johns Hopkins Institutions Office of Health, Safety and Environment.
Hospitals without a university association may not have such an extensive program.
However, many hospitals do have affiliations with physician groups and private or public
healthcare maintenance corporations that may form a coordinated health and safety
program with consistent policies and procedures. This is beneficial because there is
less confusion over safety policies and procedures when employees transfer between
hospital administrative units or physician group practices.
Relationship to Infection Control Programs
Biosafety policies and programs for hospital employees need to be intimately
coordinated with patient-related infection control issues, including tuberculosis control,
bloodborne pathogens, waste disposal, disinfection, microbial air sampling, and medical
The biosafety staff should form a collegial working relationship with the hospital
epidemiologist and the infection control nurses because many hospital procedures to
control transmission of pathogens between patients also involve employee health
issues. The biosafety officer should be a member of the hospital infection control
committee, new product committee, and hospital safety committee.
The hospital safety committee has representation from the medical staff, nursing,
infection control, clinical engineering, facilities, safety, legal affairs, human resources,
security, materials management, employee health, and occupational injury. This
ensures that appropriate hospital functional units have the opportunity to discuss and
participate in decisions that affect both patient and employee health and safety
Advisory Functions
The biosafety division advises line managers in nursing, clinical departments, facilities
operations, housekeeping (environmental services), and hospital administration. This is
an appropriate method to effect change and provide regulatory and technical
information that may not be readily available to line managers.
Hospital administrative units may request advice before making policy decisions that
have a biosafety-related component. For example, implementation of effective
bloodborne pathogen control, tuberculosis control, and construction and renovation
programs benefit from input by biosafety and other safety divisions. Hospital staff
request biosafety advice related to selection of personal protective equipment, such as
gloves and gowns, and selection of engineering controls such as sharps containers and
waste disposal containers.
Biosafety information is communicated in weekly newsletters or newspapers, printed
brochures, policy manuals, email broadcasts, an intranet web site, and individual or
group training sessions. Sometimes biosafety information is presented to hospital line
managers who in turn disseminate the information to their staff.
Advisory and training interactions with hospital staff have a public relations component.
Care is taken to present advice and information to hospital staff at an appropriate
educational level. For example, housekeeping staff and physicians relate differently to
biosafety training information during question and answer sessions.
Biosafety staff should become familiar with hospital procedures, nursing practices and
clinical equipment so that they can relate better to hospital audiences. Previous work
experience on hospital inpatient units is helpful. Many employee safety and health
interactions by biosafety staff are closely aligned with techniques used by sales and
marketing professionals, such as good listening skills, avoiding arguments, gaining
credibility with an audience, and good oral and written communication skills.
Line Management Functions
Large hospitals, tertiary care teaching hospitals in particular, may directly involve
biosafety staff in line management functions. Some of these functions at Johns Hopkins
Institutions are discussed below.
Service Functions
The certification, decontamination, and repair of all high efficiency particulate air (HEPA)
filter-containing equipment is performed by biosafety staff. This function was recently
brought in-house after twenty-five years of supervising outside certification contractors.
This saves the institution one hundred thousand dollars per year. The biosafety staff
maintain eight hundred and thirty-four biological safety cabinets and clean air benches,
eighty-two powered air-purifying personal respirators (PAPRs), twenty-eight portable
HEPA filtration units, and thirty-two bag-in bag-out rooftop HEPA filter units. The
biosafety division certification supervisor is an accredited National Sanitation
Foundation field certifier (NSF, 1999). The biosafety staff coordinate accounting and
service functions directly with line managers. This service involves equipment database
management, sending out annual certification reminders to HEPA equipment owners,
making appointments, and receiving payment for certifications, decontaminations, and
repairs of HEPA filter containing equipment.
Training and Education
The biosafety staff present regularly scheduled training sessions covering subjects such
as bloodborne pathogens, tuberculosis control, packaging and shipping of infectious
substances and diagnostic specimens, and occasionally sessions on the proper use of
biological safety cabinets, aseptic technique, laboratory practices, and design of
containment facilities. Hospital functional units often request unit-specific biosafety
training. This training is often related to regulatory requirements, such as bloodborne
pathogens and tuberculosis control programs.
Functional units requesting training include support associates (nursing aides), facilities,
housekeeping, physician credentialing (risk management), clinical laboratories, clinical
engineering, clinical trial units, materials management, security, selected nursing units,
and physician groups.
Hospital safety surveys performed by biosafety staff or a trained safety officer are taken
seriously by the hospital administration. The surveys are used to tabulate information
for Joint Commission on the Accreditation of Hospitals (JCAHO) Environment of Care
surveys. The functional units send a representative to the surveys so line management
issues can be handled on the spot. A representative from hospital facilities also
participates in these surveys so that facility safety issues will be addressed promptly.
In 1989 the hospital had seventy-two clinical unit laboratories located in nursing unit
soiled utility rooms. Gram stain racks and reagents, urine centrifuges, and
microhematocrit centrifuges were located in these unit laboratories. Most of these unit
laboratories were closed because quality control of test results was not well
documented. STAT testing was moved to a twenty-four hour, centralized clinical
laboratory. Closing most clinical unit laboratories reduced the biosafety staff time
devoted to hospital laboratory surveys.
Record Keeping
In 1989 a database system was built to maintain safety survey and training records at
Johns Hopkins Institutions. The safety database was expanded in 1992 to include
employee health data. Thus enhancing the coordination between the employee health
clinic, occupational injury clinic, and safety training activities. Functional unit
administrators receive regular updates of their employees’ attendance at safety training
sessions. This relational database is routinely updated from the hospital and university
mainframe computer payroll systems. This ensures accurate tracking of all employees,
even when they move between functional units. The database continuously expands,
fifty-seven thousand active and former employees as of 1999, because training records
are maintained after employees leave Johns Hopkins Institutions.
Performance Measurement
Information on employee and functional unit compliance with safety policy and
procedures is regularly sent to each administrative unit and reported to a joint hospital-
university safety committee (Joint Committee for Health, Safety, and Environment).
Occupational injury data is also kept in a database and reported to the joint safety
committee. Occupational injury and safety incident data are used to track employee
functional unit safety compliance and to identify tasks being performed that resulted in
an occupational injury. The databases are used to evaluate performance by analysis of
injury rates and training compliance. Quarterly and annual reviews of this information
are used to determine where corrective actions are needed to health and safety
Biosafety Related Advisory and Regulatory Organizations
Biosafety staff awareness of numerous guidelines and standards that apply to hospital
settings enhances biosafety advice and support provided to hospital administrative units
and employees. Organizations that supply hospital-related guidelines or regulatory
information are described below.
The American Biological Safety Association (ABSA) fosters recognition of biological
safety as a distinct scientific discipline, establishes a forum for exchange of information
on biological safety, and provides an organization that recognizes the needs, and
represents the interests of, persons in biological safety. Its web site, (as of 28 May 1999), has many biosafety documents, including the
location of an independent, biosafety email subscription service. ABSA also
acknowledges biological safety professionals with two registries; Registered Biological
Safety Professional, and Certified Biological Safety Professional.
The American College of Occupational and Environmental Medicine (ACOEM)
published guidelines in 1999 (Hospital Employee Health, 1999) suggesting that
physicians working in employee health services should be board certified in
occupational and environmental medicine and participate in relevant ongoing continuing
medical education. The official version of the ACOEM guidelines is published on the
internet at (as of 26 May 1999). An understanding of state
workers' compensation laws, occupational safety and health regulations and
accreditation requirements are useful to successful implementation of an employee
health and safety program. The web site, (as of 30 March 1999),
provides updated information relevant to occupational medicine.
The Americans with Disabilities Act (ADA 1991) requires that job descriptions include
job functions that permit pre-placement examiners to determine whether a new
employee can work with hazards (biohazards in this case) with or without reasonable
accommodations. This may involve medical surveillance, proper use of personal
protective equipment, and appropriate engineering controls.
The American Conference of Governmental Industrial Hygienists (ACGIH) provides
biosafety-related guidelines for indoor microbial counts as a measure of air quality. This
is a good source of information on industrial hygiene and general health and safety.
The web site, (as of 30 March 1999), provides information that
crosses between the disciplines of biosafety and industrial hygiene.
The Association for Professionals in Infection Control and Epidemiology (APIC) is an
important source of biosafety-related information that can help biosafety staff maintain a
timely dialog with Infection Control staff on issues of interest to them. The association
has guidelines on standard precautions, bloodborne precautions, airborne isolation,
personal protective equipment, disinfection, and engineering controls. The web site, (as of 30 March 1999), has extensive infection control information.
The American Society for Healthcare Engineering (ASHE) of the American Hospital
Association (AHA) provides information on healthcare facility management, engineering,
facility design, construction, safety management, and regulations affecting healthcare
facilities. The ASHE web site, (as of 27 April 1999), maintains
updates on topics relevant to facility and safety operations.
The American Society for Microbiology (ASM) represents twenty-four disciplines of
microbiological specialization plus a division for microbiology educators. This is the
oldest and largest single life science membership organization in the world. The ASM
web site, (as of 26 March 1999), has many layers of microbiological
information, including biological safety. The American Academy of Microbiology also
administers a Specialist Microbiologist board exam in Biological Safety Microbiology.
The Bureau of National Affairs (BNA) publishes a Health Care Facilities Guide (BNA
1998) that is frequently updated as new guidelines and regulations are published. This
is an excellent source of reference information for hospital biosafety staff.
The Centers for Disease Control and Prevention (CDC), an agency of the Department
of Health and Human Services, has a wealth of information pertinent to hospital policies
and procedures including guidelines for prevention of transmission of Mycobacterium
tuberculosis in healthcare settings (CDC 1994). The CDC publishes many guidelines
that are usually adopted by hospitals. The CDC also publishes a biosafety guideline for
laboratories in collaboration with the National Institutes of Health. The fourth edition of
the CDC/NIH Biosafety in Microbiological and Biomedical Laboratories (BMBL) is
available from the Government Printing Office (CDC 1999).
A Guideline for Infection Control in Health Care Personnel, published by CDC and the
Hospital Infection Control Practices Committee (Bolyard 1998), updates and replaces
previous editions. This guideline provides biosafety staff with information ranging from
employee health clinic management and policies to the epidemiology of infections
transmitted to healthcare workers, and how to effectively prevent these transmissions.
Biosafety practitioners should subscribe to the CDC Morbidity and Mortality Weekly
Report either by email or traditional mail. These reports are often the first place that
public health professionals and health care workers can receive factual biosafety
information about infectious disease outbreaks, characteristics of microbial pathogens,
and guidelines for handling these pathogens in clinical and laboratory environments.
The Department of Transportation (DOT) shipping regulations, with proposed changes
(DOT 1998), and the international dangerous goods regulations published by the
International Civil Air Organisation (ICAO) are being enforced more stringently than
ever. The IATA Dangerous Goods Regulations, published by the International Air
Transportation Association (IATA 1999) every January, provides a quick reference to
these regulations. Regulators are paying more attention to how hospitals and clinics
package and ship infectious substances, diagnostic specimens and chemicals such as
formalin, ethanol, dry ice, etc. Shippers must declare all dangerous goods and other
regulated materials, or face fines and criminal penalties. This awareness has increased
because some private overnight shipping companies notify the DOT’s Federal Aviation
Administration (FAA) when they discover any improper shipping practice. Biosafety
officers need to be aware of these Dangerous Goods Regulations in order to assist
hospital personnel with their shipping needs and to provide DOT shipping training.
The Environmental Protection Agency (EPA) regulates the use and disposal of
chemicals, such as hospital disinfectants and pathology laboratory chemicals. Each
state has statutes that meet or exceed EPA regulations for transport, treatment,
storage, and disposal of hazardous materials, including chemicals and medical waste.
Although the states regulate medical waste treatment and disposal, EPA regulations are
adopted by the states for the permitting of landfills, medical waste incinerators, and
pathologic incinerators. The EPA web site, (as of 26 May 1999),
has a search engine that will speed up searches of a large database of information
The Joint Commission on Accreditation of Healthcare Organizations (JCAHO) is a
predominant force in the hospital industry. The web site, (as of 30
March 1999), has information and links to government and professional healthcare
associations and other providers of information. Biosafety-related issues are addressed
in the JCAHO Environment of Care standards. The JCAHO now publishes an official
newsletter covering this subject (JCAHO 1998). These standards cover areas such as
safety, security, hazardous materials and waste, emergency preparedness, life safety,
medical equipment, and utility systems. Biosafety staff participate in the planning and
implementation of policies involved with JCAHO standards that address safety,
hazardous materials, medical waste, and emergency preparedness.
The Association of Occupational Health Professionals in Healthcare has asked JCAHO
to consider “stand-alone standards” specific to employee health departments. (Hospital
Employee Health 1999). Topics suggested for the proposed standards include “health
assessments; recognition, evaluation, and control of occupational health and safety
hazards; evaluation, treatment, and case management of occupational injury and
illness; surveillance, prevention, and control of infection; management of occupational
health information; education; and health promotion and wellness”.
Hospital clinical laboratories follow guidelines and standards promulgated by the
National Committee for Clinical Laboratory Standards (NCCLS). Its web site, (as of 30 March 1999), provides information on standards
developed for clinical laboratory procedures as a result of consensus among
laboratorians in industry, government, and academic institutions.
The National Institute of Occupational Safety and Health (NIOSH), a division of the
Department of Health and Human Services, reports to the CDC. This agency became
more visible to the healthcare community when tuberculosis prevalence increased
during the early 1990’s. NIOSH is an educational organization that funds research and
training at universities. NIOSH has the technical capability to research areas of interest
to the protection of employees and to develop toxicology and employee health
guidelines that may become OSHA standards. NIOSH publishes a list of approved N95
and HEPA filtered respirators for use by healthcare workers entering airborne isolation
rooms. Hospital biosafety staff will find the NIOSH guideline for evaluating and using
sharps containers to be useful, particularly if their hospital is considering a change in
sharps containers (NIOSH 1998).
Its web site, (as of 26 May 1999), is a good
reference source for technical information related to biological safety.
The National Safety Council (NSC) provides traditional safety and health information
applicable to hospital settings. Its web site, (as of 31 March 1999),
provides ordering information for books and manuals. The NSC has become involved
in biosafety-related issues pertinent to hospitals, such as occupational safety and safety
The NSF International (NSF) is a third party certifier of products and services. Its
web site, (as of 31 March 1999), is a good resource for standards
and approved products relevant to hospitals. Biological safety cabinets are evaluated
and listed according to NSF Standard Number 49 (NSF 1992), considered the industry
The Department of Labor, Occupational Safety and Health Administration (OSHA)
increased its visibility in hospitals when the bloodborne pathogen standard was
promulgated in 1991 (OSHA 1991) and the revised respiratory protection standard was
published in 1998 (OSHA 1998a). Its web site, (as of 31 March
1999), has an extensive library of standards, documents and resources. Enforcement
of the bloodborne pathogens standard is either by federal OSHA inspectors or by state
occupational health inspectors in OSHA-cooperating states that have an OSHA
approved statute.
OSHA is now collecting injury and illness information from hospitals that may be used to
determine which employers will be inspected in subsequent years. Hospitals with
higher than normal injury or illness records may become a target for more frequent
inspections. In 1999, OSHA inspections are in response to employee complaints.
The Society for Healthcare Epidemiology of America (SHEA) fosters the development
and application of the science of healthcare epidemiology. SHEA has published
recommendations for management of health care workers infected with Hepatitis B
Virus (HBV), Hepatitis C Virus (HCV), Human Immunodeficiency Virus (HIV), or other
bloodborne pathogens (SHEA 1997). This organization is a good information resource
for hospital epidemiologists, infection control practitioners and biosafety professionals.
Its web site, (as of 28 May 1999), contains
information about two journals published by SHEA, Infection Control and Hospital
Epidemiology, and Clinical Performance and Quality Health Care.
Biosafety Related Administrative Programs
Airborne Isolation
Airborne isolation is the term used at Johns Hopkins Hospital to designate the isolation
procedure used to manage patients with known or suspected infectious Mycobacterium
tuberculosis (TB) disease.
Biosafety staff involvement includes advice on the design of negative pressure isolation
rooms connected to roof top bag-in bag-out exhaust HEPA filters. Biosafety staff check
the performance of these filters every three months. Separate magnehelic pressure
gauges across pre-filters and HEPA filters are used to measure air pressure differential,
an indication of filter loading with dirt. When the pressure increase across a filter
exceeds a pre-determined level, the biosafety staff replace pre-filters and also replace
and certify new HEPA filters when required. Exposure risks to biosafety staff during
filter removal are minimized by the bag-in bag-out procedure, and because they wear
half-face HEPA cartridge, negative pressure respirators.
Biosafety staff certify and maintain powered air purifying positive air pressure HEPA
respirators (PAPRs) used by hospital staff when entering airborne isolation rooms. The
PAPRs are checked every month for proper airflow and repairs are made as necessary.
There are seventy-two PAPRs permanently located at nursing units and procedure
rooms where TB patients are treated. Additional PAPRs are available from the
biosafety staff for emergency use in other hospital locations.
Biosafety staff also certify and repair portable HEPA filter units that are wheeled into
airborne isolation rooms to supplement the particle dilution effect of room exhaust. The
portable HEPA units are about the size of a small refrigerator and are delivered by
biosafety staff to ensure that they are placed in the proper location in patient rooms,
usually just inside and perpendicular to the door. There are twenty units permanently
placed in areas where there is a perceived need for additional HEPA filtration, such as
airborne isolation rooms and intensive care units for pediatric patients with low white
blood cell counts. The portable HEPA units are checked every three months for proper
airflow when the pre-filters are replaced. They are certified annually and every three
years they are decontaminated so that the HEPA filters can be replaced and certified by
an aerosol leak test method.
Biological Air Sampling
This subject has received much attention by hospital staff because energy conserving
building construction during the 1970's produced indoor air quality issues that were
widely publicized. Therefore, this section covers microbial air sampling issues in detail.
Microbial air sampling is performed by request from industrial hygiene, infection control
and functional units in the hospital. Biosafety staff use a Biotest RCS Plus centrifugal
air sampler. The sampler has a microprocessor-controlled motor speed and operates
on a rechargeable battery. The sampler runs for about four minutes at each sample
site, a typical run time recommended by the manufacturer. Each sample collects one
hundred and sixty liters of air.
Airborne fungal counts are requested more frequently than airborne bacterial counts.
Requests are generally related to indoor air quality concerns including allergies.
Inpatient oncology units occasionally request sampling for potentially pathogenic fungi
such as Aspergillus fumigatis. One year, biosafety staff collected over three hundred
and forty samples at oncology patient units and found no evidence of fungal
amplification (multiplication of fungal colonies causing increased numbers of airborne
fungal spores).
Only one office area was found to contain fungal counts over five hundred colony
forming units per cubic meter during the last ten years. Ironically, this sample was
obtained at the second floor of the former safety office.
All microbial air sampling is accompanied by a contemporaneous outside control.
Generally, outside control colony forming units are an order of magnitude higher than
the inside colony forming units. Usually employees conclude that the outside
environment is more problematic than their inside environment when they see the
control fungal counts.
Attention to the interpretation of indoor air sample counts is an important biosafety
issue. Misinterpretation of results may cause unwarranted concern among employees.
The significance of a few colony forming units (cfu) from indoor air samples must be
compared to outdoor colony forming units because fungi enter buildings in supply air. If
there is fungal amplification indoors, the colony forming units may then be greater than
A more useful measure of airborne contamination of the indoor environment can be
obtained with a recording multi-channel laser particle counter operating over an
extended time period. The biosafety staff has used this method to demonstrate the
significant contribution to indoor particle levels by carpeting. Carpet is now permanently
removed from patient areas during renovations.
An article using a statistical approach to identify the influence of various factors on the
data reproducibility and air sampling confidence limits stated that “there is no legal
standard for sampling methods for airborne microorganisms" (Straja and Leonard,
1996). Also, "the sampling -period can not be long because the collection surface dries
or the agar deforms beneath an impaction jet.” Straja and Leonard (1996) chose
Biotest RCS equipment because of cost, commercial availability, portability, ease of
operation, and inconspicuousness. They sampled for thirty seconds, sixty seconds, and
one hundred and twenty seconds in the same room using forty replicate samples with
four teams of sampling personnel. They presented a statistical analysis of the data and
concluded that “all quantitative conclusions involving the number of colony forming units
should be reached considering that their distribution is log-normal rather than normal."
Straja and Leonard (1996) stated that Biotest RCS air-samplers seem to be reliable in
the sense that different sampling-periods give practically the same information.”
Plog (1996) states that “impaction directly onto an agar-based culture medium is the
most commonly chosen method to collect culturable bacteria and fungi. Hand-held,
battery-operated samplers have the advantage of portability and independence from a
power supply, although they sample at fairly high flow rates (forty to eighty liters per
minute), these devices are quiet and fairly inconspicuous.”
The American Conference of Governmental Industrial Hygienists (ACGIH 1989)
recommends that “the commercially available centrifugal impactor is quite portable and
inconspicuous, thus making it an obvious choice where samples must be taken with
minimal disturbance of occupants.” They state that the device cannot be calibrated
mechanically, citing a 1983 article (Macher and First 1983). However, a new Biotest
RCS Plus model produced in 1991 has an optional mechanical calibration device.
Chatigny et al. (1989) state that there are “no widely accepted guidelines for an
allowable or desirable microbiological burden in the air, and little consensus on an
‘indicator organism’ to demonstrate contamination of air in the same way that a coliform
count is used to reflect water quality.”
The Environmental Health Directorate of Canada (Health Canada 1995) states that
“vacuum/culture devices such as RCS, Andersen, and slit-to-agar samplers are
recommended for air sampling in public buildings and that current Health Canada
guidelines are based on four-minute samples with the RCS .”
Jensen et al. (1992) made an important point about the earlier model (Biotest RCS)
used in their investigation. The Biotest RCS actual flow rate was experimentally
determined to be two hundred and ten liters per minute by Macher and First (1983).
Jensen et al. (1992) pointed out that the manufacturer’s suggested forty liters per
minute flow rate be used for calculated recovery of microorganisms because the high air
velocity in the centrifugal impaction chamber reduced the capture efficiency of particles
smaller than four micrometers.
The new Biotest RCS Plus has a redesigned sample chamber that minimizes
turbulence by separating the intake and exhaust streams via a flow-through sample port
while components of the rotor assembly (impeller blade, drum, and agar strip) all rotate
simultaneously, further minimizing turbulence. The RCS Plus yields a high collection
efficiency for viable particles across a wide range of particle sizes and achieves an
eighty-five percent efficiency for two micrometer size particles, and over ninety-eight
percent efficiency for four micrometer and larger size particles.
Sample volume information from a literature review (unpublished information) indicates
that use of twenty-eight liter per minute samplers run for five to fifteen minutes is the
most common practice. Some investigators get around the usual sampling volume
limitations by running their samplers over and over at the same location with new
culture media agar strips each time. Then they incubate these multiple samples, count
colonies and add all of the results together to give the colony forming units for a large,
theoretical air volume sample.
Arnow et al (1991) found mean counts of two tenths per cubic meter of Aspergillus
species before an outbreak among immunocompromised patients, and a mean up to
two and two-tenths colony forming units per cubic meter during the epidemic period.
They used a slit sampler operated at one hundred and eighty liters per minute for three
minutes. Goodley et al. (1994) added sample counts obtained over a long time period
and expressed the results as total colony forming units per cubic meter per month.
They also found that even when the A. fumigatus counts in the air were as high as four
colony forming units per cubic meter “none of the colonized patients subsequently
developed infection related to Aspergillus species and none had persistent
CDC surveillance guidelines (CDC 1997) for aspergillosis have “no recommendation for
performing routine, periodic cultures of devices, air samples, dust, ventilation ducts, and
filters in rooms occupied by high-risk patients.” This is an unresolved issue, according
to CDC. The guidelines also recommend that if a case of nosocomial aspergillosis
occurs, “collect environmental samples from potential sources of Aspergillus species,
especially those sources implicated by epidemiologic investigation, by using appropriate
methods (e.g., use of a high-volume air sampler rather than settle plates.” These
guidelines define ‘appropriate methods’ as use of the Biotest, Andersen, and slit-to-agar
samplers, which are considered high volume samplers. This is a common designation
for samplers that operate in an air flow range of twenty-eight liters per minute to sixty
liters per minute, with sample times ranging from a few minutes up to sixty minutes.
Some hospitals have an immediate reaction to cases of nosocomial aspergillosis and
begin intensive air sampling, only to flood the clinical lab with samples and come up
with no useful information. Therefore, caution is advised.
Biological Safety Cabinets
Biological safety cabinets (BSCs) are used in the hospital by the pharmacy, in-vitro
fertilization clinic, procedure rooms, and clinical laboratories. BSCs should not be called
"hoods" because most individuals confuse this term with chemical fume hoods. The
biosafety division approves purchases of all HEPA filter-containing equipment at Johns
Hopkins Institutions. Purchasing sends purchase orders to the biosafety division before
purchase orders are sent.
A detailed, performance oriented biosafety cabinet specification was collaboratively
written to ensure that vendors submitting bids for equipment that was listed by NSF 49
and would pass motor/blower specifications under HEPA filter loading conditions (Jack
Wunder, personal communication).
Bloodborne Pathogens Control Program
Biosafety division staff involvement began in 1988 with a training seminar for hospital
staff presented by the infectious disease department, biosafety division, HIV
researchers, nursing department, infection control department, and hospital
Bloodborne pathogens continues to involve biosafety staff on many fronts, primarily
training and education. The bloodborne pathogen control policy, training brochures,
posters, written handouts, and other materials were collaboratively produced by the
biosafety staff with input from employee health, occupational injury, nursing, infection
control, housekeeping, and facilities.
Early training materials for the entire hospital staff consisted of a multiple page brochure
that covered most program components of the policy and a forty-minute videotape
produced by a video production company for Johns Hopkins Institutions.
Physician training started with a self-study brochure and a national board-style test that
physicians completed and returned to the biosafety office. Occasionally, physician
office staff would call to find out how they did on the test, thus explaining why some
physicians scored below forty percent. Currently, the biosafety officer presents
bloodborne pathogens training and policy updates during risk management seminars
that are required every two years for physicians with hospital privileges.
Nursing staff training is accomplished via self-study manuals placed at all nursing
stations. Nurses read these manuals, take a quiz and return it to nursing administration.
Training records are then forwarded to the Office of Health, Safety and Environment for
database entry.
Support associates have increased responsibility for routine patient care activities.
These individuals receive bloodborne pathogen training by biosafety staff at least once
a year. Training sessions involve the use of handouts, but the primary training involves
a question and answer session directed toward topics that are important to support
associate duties. Topics include Hepatitis B Virus (HBV) vaccination, the post exposure
hotline, personal protective equipment, disinfectants, and waste disposal.
New hospital staff, including nurses, receive bloodborne pathogen training by the
employee health division which gives employees the opportunity to schedule HBV
vaccination, tuberculin testing, and antibody testing as appropriate.
New university staff, often assigned to hospital areas, receive information about the in-
depth bloodborne pathogen training sessions presented twice every month. Employees
that have potential occupational exposure to human blood, internal body fluids, unfixed
tissue, human tissue cultures, or animals inoculated with human materials come to
these training sessions. Training includes procedures to follow if exposed, such as
washing the exposed site with soap and water or water irrigation for eye exposures,
calling the employee exposure hotline, post-exposure prophylaxis for serious
exposures, and confidential clinical case management after an exposure. Eight minutes
of video summarizing important training elements of the policy is followed by
discussions of the differences between exam and non-sterile surgical gloves for patient
care and research laboratory use, respectively. Comparisons between latex, vinyl and
nitrile gloves include a discussion of potential allergies from cornstarch powder in latex
gloves. Question and answer sessions often deal with disinfectants, wearing gowns
with knit gloves in laboratories, hazard signage, survival of bloodborne pathogens in the
environment and recently, notification of packaging and shipping certification classes.
Clean Air Benches
Clean air benches (CABs) are becoming scarce in hospital settings because they offer
no personal protection. Their remaining use is assembly of sterile packages for patient
care. Reverse flow clean air benches are used in patient settings to deliver aerosolized
medications. The patient sits at the reverse flow clean air bench during aerosol
delivered medication. The HEPA filter at the rear of the clean air bench captures
aerosols that escape during treatment.
Cleaning and Disinfection
The biosafety staff recently worked with infection control, nursing, housekeeping, legal
affairs, and clinical engineering to replace an alkaline, benzyl ammonium chloride spray
disinfectant with an organic solvent base that allegedly damaged plastic-containing
clinical equipment. The decision was made to return to a one to ten dilution of
household bleach for laboratories, a one to fifty dilution for clinical areas with no
dispensing station, and a one to twenty dilution for areas with dispensing stations. All
dilutions will have one month expiration dates. The stability these dilutions is enhanced
by keeping the solutions at about pH of 8.0. A recent review of disinfectant use in
hospitals provides additional background (Rutala 1996).
Cleaning is the physical removal of organic material or soil from objects. It must be
accomplished with water, mechanical action, and detergents. Disinfection is the killing
or inactivation of specific target microorganisms. The efficacy of disinfection is affected
by a number of factors, including the type and level of microbial contamination,
presence of organic material, the activity of the disinfectant, and disinfectant contact
Biosafety staff collaborate with infection control, nursing, housekeeping, and industrial
hygiene to develop policies for routine disinfection of environmental surfaces,
decontamination of blood spills, and proper use of sterilants for semi-critical and critical
Disinfectants are divided into three hierarchical categories of antimicrobial activity. Low-
level disinfectants kill most bacteria, and some fungi, and inactivate some viruses. They
do not reliably kill Mycobacterium tuberculosis or bacterial spores. Intermediate-level
disinfectants kill most bacteria, including Mycobacterium tuberculosis, and most fungi.
They inactivate most viruses and kill some bacterial spores. High-level disinfectants
destroy or inactivate all microorganisms, including most bacterial spores.
Low level disinfectants, such as quaternary ammonium compounds, are used for non-
critical items that come into contact with intact skin but not with mucous membranes; for
example, blood pressure cuffs. These general purpose hospital disinfectants have
hundreds of different brand names. Environmental surfaces, such as floors, walls, and
tables, are usually not involved in the transmission of infections. A detergent with low-
level disinfectant activity is sufficient for general cleaning of these surfaces.
Intermediate level disinfectants, such as sodium hypochlorite (household bleach),
iodophores, hydrogen peroxide, and phenolics, are used on semi-critical items such as
hydrotherapy tanks and thermometers. When environmental surfaces are significantly
contaminated by large quantities of blood, an absorbent drape or paper towel should be
placed over the contaminated material and an intermediate level disinfectant should be
sprayed or poured on the drape or paper towel. After 10 minutes of exposure the drape
or paper towel should be discarded, followed by more intermediate-level disinfectant
applied to the surface.
High level disinfectants, such as activated 2% glutaraldehyde, are used for semi-critical
items that come into contact with mucous membranes or non-intact skin. Examples of
items that require high-level disinfection are respiratory therapy equipment,
arthroscopes, laparoscopes, and endoscopes.
Construction and Renovation
Biosafety issues involve containment of dust, microbial spores, or other microbial
material that may become airborne during construction and renovation. Biosafety staff
collaborated with industrial hygiene, infection control, and facilities design and
construction to develop a policy that provides dust containment when work is performed
in or near patient or clinical areas.
The containment policy is similar to a typical asbestos abatement policy but without
intensive air sampling. Plastic sheeting is taped to surfaces around construction areas
and plastic sheet double entry systems are constructed. A HEPA filtration system is
sometimes used to provide negative air pressure inside construction areas and to trap
dust particles in HEPA filters. HEPA filtration is often used during construction near
patient sensitive areas such as operating rooms, intensive care units, and oncology
A containment procedure with recommended personal protective equipment was
developed for entry into supply and exhaust ductwork in patient areas and includes a list
of appropriate personal protective equipment. This became an issue for oncology and
transplant patient areas with built in HEPA filtered air systems above dropped ceiling
tiles. When a patient room HEPA filter or blower fan must be replaced or cable must be
pulled above dropped ceilings, plastic containment is built around the repair area.
Employee Health Management
Biosafety staff coordinate training information with the employee health clinic and the
occupational injury clinic to ensure accurate health information is delivered to
employees. Biosafety related information is reviewed by employee health and biosafety
Employees learn about the employee health clinic location and office hours during
orientation. The clinic typically handles vaccinations, tuberculin skin tests, respirator
medical surveillance, confidential antibody testing for bloodborne pathogens, and other
medical surveillance. The clinic has several waiting rooms, examination rooms, and
treatment rooms.
Eye, Face and Body Wash
A drench hose with a spray head that produces an aerated spray six inches high is
located at most sinks in laboratories and soiled utility rooms. This eye, face and body
wash unit has a vacuum breaker and a cold potable water flow control valve. New
laboratory areas are also fitted with a double head eyewash station connected to
potable water lines.
Hand washing and Antisepsis
Biosafety issues include transmission of microorganisms to and from hospital staff.
Nursing and infection control departments provide hand washing information with self-
study packets. This information is included in biosafety training for bloodborne
Routine hand washing in patient care areas utilizes an antiseptic chlorhexidine
gluconate soap. Other hospital areas and laboratories utilize a mild lotion soap. Foam
alcohol or germicidal hand rinse is used for waterless hand cleaning.
HEPA Filter Certification and Maintenance
The biosafety staff certify, decontaminate, and repair all biological safety cabinets
(BSCs) and clean air benches (CABs). According to policy, all HEPA-filter containing
equipment must be certified at least annually. Pharmacy equipment is certified every
six months. Functional unit directors are notified by memorandum when their
equipment is due for certification.
Each functional unit pays for replacement ultraviolet (UV) germicidal lamps, and are
responsible for discarding UV lamps at chemical waste drop off areas. Routine
certifications and decontaminations are scheduled at least two weeks in advance.
Highest service priority is assigned to repair of non-functioning units, followed by
fluorescent and UV lamp replacement, decontamination, filter changes, and certification.
Isolation Rooms
The CDC TB Guidelines (CDC 1994) caused most hospitals to renovate existing patient
rooms or construct new rooms with a negative air flow with respect to surrounding
areas. Most airborne isolation rooms at Johns Hopkins Hospital have bag-in bag-out
HEPA filter systems on isolation room exhausts. Isolation rooms were placed in the
emergency department, medical inpatient floors, pediatric and adult intensive care units,
and bronchoscopy suites.
These rooms have an air pressure sensor that alarms when the negative pressure
differential is less than 0.002 inches of water pressure. Since many isolation rooms
have large sliding doors to allow passage of hospital beds, the alarms sound every time
the door is opened and negative pressure is lost. Clinical staff often turn off the audible
alarm when they need to go in and out of these isolation rooms. Room pressure
sensing systems do not provide assurance of negative air flow as efficiently as a visible
indicator such as a ribbon or yarn telltale mounted in the isolation room door.
Directional air flow is actually facilitated by permitting some air from the hall to infiltrate
into the isolation room.
Latex Hypersensitivity
An excellent review of latex glove manufacturing, the clinical signs and symptoms of
latex allergy, and management of latex allergies was recently published (Yunginger
A study of the prevalence of latex sensitization among one hundred and sixty-eight
anesthesiologists and nurse anesthetists found 2.4 % of the individuals had latex allergy
with clinical symptoms and 10.1% had latex sensitization without clinical symptoms.
Therefore, "hospital employees may be sensitized to latex even in the absence of
perceived latex allergy symptoms" (Brown et al 1998). Powdered latex gloves contain
latex allergens attached to cornstarch powder. A clinical test involving puncturing of the
skin on the hand immediately prior to glove application was shown to provide an
objective biologic measurement of latex allergen sensitization in latex-allergic subjects
(Hamilton and Adkinson 1997).
Use of powdered gloves has been curtailed in all hospital areas except for some
surgical procedures. The hospital recently switched from latex to vinyl examination
gloves on patient care units to reduce the probability of latex allergies among patients
and healthcare workers. Latex balloons and toys are not permitted in the hospital.
Medical Waste Containers
Patient rooms have red bag lined wastebaskets. Soiled utility rooms and laboratories
also have red bag lined biohazard boxes for disposal of glass, hard plastic items, closed
sharps containers, and other medical waste. Clinical laboratories have larger bench top
and floor plastic disposal containers with drop through holes in the top for discarding
larger sharps. Cultures of microorganisms are decontaminated by autoclave before
disposal into the medical waste stream.
The Johns Hopkins Hospital patient area sharps containers were recently changed from
a direct drop in design to a mailbox design that closes automatically when the container
is full. Injuries associated with sharps disposal into these new containers will be tracked
to determine whether they are safer than the previous drop in style sharps containers.
Mailbox sharps containers are less useful than drop in styles for disposal of butterfly
needles and tubing, very long needles, and pasteur pipettes because these objects
must be manipulated in order to fit them into a mailbox opening sharps container.
NIOSH published a useful guide to sharps containers including such details as how they
should be mounted (NIOSH 1998).
All red bag and boxed medical waste is trucked to a local medical waste incinerator.
The State of Maryland medical waste statute requires that all medical waste be
decontaminated and rendered unrecognizable before it can be landfilled.
Needle-less IV Systems
Needlestick prevention has become a topic of interest recently to regulators such as the
FDA, NIOSH, OSHA, and professional associations such as APIC. Needle-less
systems are recommended for non-skin puncturing procedures. OSHA has received
responses from a request for information (OSHA 1998b) on engineering and work
practice controls used to eliminate or minimize the risk of occupational exposure to
bloodborne pathogens due to percutaneous injuries from contaminated sharps (OSHA
1999a). Based on the responses, OSHA plans to revise the record keeping rule so that
all injuries from contaminated needle and sharps are recorded on OSHA logs. They will
also revise the bloodborne pathogens compliance directive to reflect available safer
technologies. Needlestick and sharps injuries are expected to be on the OSHA
regulatory agenda for late 1999.
Occupational Injury Management
The Johns Hopkins Hospital implemented a needle stick hotline for bloodborne
pathogen exposures in 1990. After a slow start, healthcare workers call the hotline with
increasing frequency each year. The hotline is manned by an occupational medicine
physician or physician’s assistant during business hours, and by infectious disease
fellows on call at other times. The hotline exposure reporting frequency increased with
publication of CDC guidelines for post exposure prophylaxis in 1996 (CDC 1996) and
increased again when the CDC published the second edition of the guidelines (CDC
The hospital’s twenty-four hour pharmacy dispenses the first dose of prophylactic
drugs if the exposure is considered serious and the healthcare worker decides to start
the twenty-eight day course of antiviral therapy. Healthcare workers of childbearing age
are given a pregnancy test before they can start post exposure prophylaxis.
Biosafety staff investigate employee incidents such as exposures related to waste
disposal, handling of sharps, handling of patient specimens, and unsafe practices with
clinical and laboratory equipment.
Permanent HEPA Filtration
There is a trend to provide HEPA filtered supply air in oncology and transplant patient
rooms. The biosafety division assists with the proper placement of HEPA filter units.
For example, HEPA filters for patient room supply air should be mounted in the ceiling
of each patient room. The filter units should be designed so that they can be dropped
down and replaced inside a patient room, thus minimizing the spread of dust and debris
generated during filter replacement to adjacent areas.
HEPA filters should be connected directly to each room's supply air duct. Room air
should be single pass and exhausted to the outside without recirculation. Some
situations may require that the supply air be mixed with some recirculating exhaust air
from the same room to reduce the costs associated with heating and cooling outside air.
HEPA filters should be bench tested for leaks in the filter media and around the edges
of the filter frame before the filters are mounted in the ceiling and placed into service.
There have been instances of new HEPA filters with leaks around the frame or the
media put into service at some healthcare facilities. Filter leaks can be found using
equipment recommended by the NSH Standard 49 procedure (NSF 1992).
Portable HEPA Filtration
Johns Hopkins University designed portable HEPA filters (Tepper et al. 1993) are
moved to appropriate places by biosafety staff. Portable HEPA filter units are used in
two different hospital areas. They are used in patient rooms for airborne isolation when
negative pressure HEPA filtered exhaust rooms are not available. They are also placed
in pediatric intensive care rooms for patients with a low white blood cell count and
therefore may benefit from a reduced airborne dust in their room.
Portable HEPA units are permanently located at nursing units that use them constantly
and in areas such as emergency waiting rooms to provide additional removal of
Before they were used, the portable HEPA units were evaluated by industrial hygiene
staff in patient rooms with an aerosol generator and particle counter to ensure that the
units provided increased relative air changes in patient rooms, and effectively removed
aerosolized particles. Tests with smaller, commercially available portable HEPA units
often did not effectively remove particles from patient rooms. Therefore, hospitals
should perform in place testing with a particle counter before portable HEPA units are
placed into service.
Pre-filters on these portable HEPA filter units are replaced every three months by
biosafety staff. This greatly extends the life of the HEPA filters, which usually last for
two to three years of continuous operation. The airflow output of each portable unit is
also checked with a hot wire anemometer. When the airflow becomes less than eighty
percent of the manufacturer's specified air velocity, the unit is placed in a plastic bag,
decontaminated with formaldehyde gas, and new HEPA filters are installed. Newly
installed HEPA filters are checked for leaks using an aerosol generator and a
photometer (the same equipment used to certify biological safety cabinets).
Healthcare workers entering TB patient airborne isolation rooms must wear a respirator
to reduce the possibility of occupational infection from aerosolized TB bacteria.
Respirator options for healthcare workers entering airborne isolation rooms was studied
by the industrial hygiene and biosafety divisions at Johns Hopkins Institutions (Schaefer
1997). Industrial hygiene and nursing staff evaluated disposable respirators, reusable
cartridge respirators, and positive air pressure respirators. Cost considerations and
acceptance by healthcare workers clearly favored the use of loose-fitting, portable
powered air purifying personal HEPA filter respirators (PAPRs). The annual cost
savings was significant because a less rigorous respiratory surveillance program could
be implemented. Fit checking was eliminated because the PAPRs were positive
pressure and loose fitting. The medical staff found the PAPRs more comfortable to
wear and more acceptable to patients than negative pressure N95 or HEPA cartridge
respirators. Acceptance of these respirators was enhanced by support from the Chief of
the Infectious Disease Department.
Respiratory Surveillance
Industrial hygiene staff fit test negative pressure respirators for employees. The
employee health clinic manages the annual medical respiratory surveillance. Biosafety
staff train healthcare workers that wear portable powered air purifying personal HEPA
respirators (PAPRs) when entering airborne isolation patient rooms. A short version of
the respiratory protection approval form was developed for these PAPR-wearing
employees because loose fitting, positive pressure respirators with no breathing
resistance have fewer medical issues.
Safer Sharps
The Food and Drug Administration (FDA), NIOSH, and OSHA jointly published a safety
advisory about potential risks from small glass capillary tubes (OSHA 1999b).
Accidental injuries occur when the capillary tubes are sealed with putty before they are
placed into a centrifuge to determine a patient's blood hematocrit. OSHA estimates that
there are two thousand, eight hundred injuries each year from glass capillary tube
breakage. The agencies recommend that capillary tubes be made of materials other
than glass, that glass tubes be wrapped in a puncture resistant film, or an alternative
method be used to measure hematocrit levels. Johns Hopkins Hospital changed to a
colorimetric method to measure hematocrit levels in 1994 because of the possibility of
injury from the microhematocrit centrifugation procedure.
OSHA and several states are in the process of adopting, regulations to increase the use
of retractable needles. Early prototypes and commercially available systems were often
not easy to use and sometimes did not work. Current systems are markedly improved.
They are now available in many different needle-syringe combinations, either empty or
pre-filled with appropriate drugs or materials. There are also retractable needle
phlebotomy systems for vacuum blood tubes used to obtain blood specimens. The
state of California passed a safer sharps law in 1998. Similar laws are being
considered in eleven other states, including Maryland.
The hazard warning signage system developed by the safety office in the 1970's for
research and clinical laboratories was revised in 1995. The system was developed to
bring uniformity to hazard warning signage used at Johns Hopkins Hospital and University.
This section will only cover biosafety-related signage used at the hospital. Hazard warning
signage informs personnel and visitors that a hazard exists in an area. Two levels of risk
have been established. The degree of hazard is indicated by the admission instructions
on a ten inch by ten inch yellow placard mounted on the wall adjacent to the entrance of a
posted area. Specific hazards are identified by two inch by two and a half inch symbols
and/or hazard warnings affixed to the placard.
The levels of risk are defined on the admittance placards. “CAUTION - ADMITTANCE TO
AUTHORIZED PERSONNEL ONLY” placards indicate that visitors and personnel not
assigned to the area must secure permission to enter from the investigator, supervisor or
administrator in charge of the area. “CAUTION - RESTRICTED AREA - ADMITTANCE
TO AUTHORIZED PERSONNEL ONLY” placards indicate that admittance is forbidden to
all except those assigned to the area unless accompanied by the principal investigator,
supervisor or administrator in charge of the area.
Text accompanying the labels specifies the conditions under which the most frequently
used biohazard warning signs will be posted. It is the responsibility of the biosafety staff to
determine the need for biohazard warning(s). The safety office posts the signage and
maintains records of posted areas. It remains the responsibility of each hospital functional
unit to list the names with work and home telephone numbers of two individuals on the
admittance placard as emergency contacts. The individuals listed must have some
familiarity with the biohazards in the posted location.
Biohazard warning labels listed with the "restricted area" text signifies admittance to
laboratory personnel only, all others must obtain permission from the laboratory supervisor
to enter the area or open containment equipment labeled as "restricted". This label is
generally used to identify refrigerators, incubators, and cabinets where biological agents or
materials are stored.
The biohazard symbol warning label without a specific hazard description is a general
biohazard warning to be used where there are multiple biological hazards, where
biological wastes are stored, and for mixed biological waste containers.
Biohazard warning labels with the "potentially infectious materials " text are used in rooms
or areas (research and clinical laboratories, certain hospital unit laboratories and utility
rooms) where human body fluids, unfixed cell tissue or organ cultures are handled for
research, diagnosis, or shipment, and equipment used for research or diagnosis with
specimens containing potentially infectious materials.
The biohazard symbol warning label with the "infectious agents" text is used in laboratories
and support areas where viral, bacterial, fungal, and parasitic agents requiring
containment at Biosafety Level 2 (BL-2) or greater are used or stored.
The Biosafety Level 2 (BL-2) label, with the appropriate biohazard warning label described
above, designates a containment level which meets the guidelines for BL-2 work practices,
safety equipment and facility design. This label is placed at clinical laboratories that
process blood and other patient specimens.
The Biosafety Level 3 (BL-3) label, with the appropriate biohazard warning label described
above, designates a containment level which meets the guidelines for BL-3 work practices,
safety equipment, and facility design. This label is placed on the wall next to door of the
clinical mycobacteriology laboratory.
A "no food and drink" label indicates that eating, drinking, smoking, handling of contact
lenses and applying cosmetics are not permitted in the posted work area because there is
reasonable likelihood of exposure to hazardous chemicals, radioactive materials, or
potentially infectious materials.
An "eye protection required" label is posted in all areas where there is a reasonable
probability of exposure by splash or spray to hazardous chemicals or potentially infectious
agents and physical hazards which could cause injury.
A "protective clothing required" label is posted when work conditions require specific
protective clothing which is beyond the standard laboratory coat or gown. Personal
protective clothing selected for this work area shall be based on an evaluation of the task
specific conditions and the hazards and potential hazards that are encountered.
Standard Precautions
Standard Precautions supplanted Universal Precautions at most hospitals following
recommendations by healthcare professional associations (Garner 1996). Portions of the
Johns Hopkins Hospital policy, developed by collaboration of biosafety, infection control,
and nursing are presented for informational purposes.
Standard Precautions apply to all patients, regardless of diagnosis. Standard
Precautions expands the coverage of Universal Precautions by recognizing that any body
fluid may contain contagious microorganisms. Standard Precautions are implemented by
donning gloves when anticipating contact with blood, all body fluids, secretions, and
excretions except sweat, regardless of whether they contain visible blood, non-intact skin
and mucous membranes.
Standard Precautions requires hand washing promptly after touching blood, body fluids,
secretions, excretions, and contaminated items, whether or not gloves are worn. Hands
must be washed immediately after gloves are removed, between patient contacts, and
when otherwise indicated to avoid transfer of microorganisms to other patients, staff, or
environments. Hands must be washed between tasks and procedures on the same
patient to prevent cross-contamination of different body sites. An antimicrobial soap is
used for routine hand washing.
Patient-care equipment that has been soiled with blood, body fluids, secretions, and
excretions must be handled in a manner that prevents skin and mucous membrane
exposure, contamination of clothing, and transfer of microorganisms to other patients and
Reusable equipment in contact with non-intact skin, blood, body fluids or mucous
membranes must be cleaned with a hospital approved disinfectant before it is used for
the care of another patient.
Sterilization Policies
Biosafety staff provide autoclave technical advice to central sterile supply and clinical
laboratories. Issues include autoclaving times for decontamination of laboratory waste,
odor control (not recommended), and selection of sterilization process chemical and
biological indicators. A rapid biological indicator was selected for central sterile supply
because results could be obtained within a few minutes, thereby permitting the rapid
release of sterile supplies for use in the hospital.
Chemical indicators show that proper temperature was reached during a sterilization
cycle. They do not provide proof that six logs (106) of bacterial spores were killed
Sterilization processes with commercially available indicators with performance
standards are; ethylene oxide, steam autoclave, gamma radiation, electron-beam
radiation, formaldehyde/moist heat, and dry heat.
Biological indicators, such as Bacillus stearothermophilus spores indicate proper
conditions for sterilization were present. This is the industry gold standard for steam
sterilizer efficacy testing. There are rapid (less than thirty seconds) biological indicators
based on a colorimetric test to confirm that a heat stable enzyme was inactivated during
a sterilization process.
When the numbers of microorganisms on environmental surfaces or equipment
(bioburden) is unknown, the most appropriate method to validate sterilization is the
overkill method. Validation by the overkill method involves demonstrating that 106
spores will be killed in a half cycle. Thus a full cycle would result in a 12 log (1012)
reduction of spores and produce a sterility assurance level (SAL) of 10-6, or a one-in-a-
million statistical chance of a non-sterile sample.
Monitoring should be performed weekly, preferably daily in hospital OR's, and after
installation or any repair. The CDC recommends that every load containing implantable
medical devices be monitored. The Association for the Advancement of Medical
Instrumentation (AAMI) recommends monitoring at least weekly, but preferably daily.
The Association of Operating Room Nurses (AORN) and the American Society for
Healthcare Central Service Professionals (ASHCSP) suggest daily monitoring. The
Joint Commission on Accreditation of Healthcare Organizations (JCAHO) recommends
that the facilities determine monitoring frequency.
Autoclaving is not recommended for dense materials. There are specific guidelines to
evaluate sterilizer efficacy using AAMI 16-towel test packs, AAMI Bowie-Dick test
packs, and AAMI challenge test packs.
Tuberculosis Control Program
The biosafety division chairs the tuberculosis control committee and writes the
tuberculosis control policy in collaboration with employee health, infection control and
nursing. The employee tuberculin testing policy is currently being revised to reflect the
low numbers of infectious TB patients in the Baltimore area. The tuberculin skin test is
given to all new employees and annually thereafter to direct patient care healthcare
workers with potential exposure to TB patients as determined by their supervisor.
Early TB control training materials consisted of a multiple page brochure that covered
most program components of the policy. Currently, the biosafety officer uses a three
panel brochure to present physician training and policy updates during monthly risk
management seminars for physicians.
Nursing staff training is accomplished by self-study manuals placed at all nursing
stations. Nurses read these manuals and take a quiz that is returned to nursing
administration that forwards the results to the Office of Health, Safety and Environment.
Nursing staff that work in TB patient areas are trained by the biosafety staff on how to
operate, clean and store PAPR equipment.
Support associates receive tuberculosis training by biosafety staff at least once a year.
Training sessions involve question and answer sessions directed toward topics that are
important to support associate duties. Topics include how TB is transmitted, the signs
and symptoms of TB disease, procedures for use of PAPR equipment, and use of
tuberculin skin testing. Support associates also complete a short version respiratory
surveillance form
Vacuum Delivery Systems
Many hospitals use vacuum delivery systems to move materials from one area to
another. Biosafety issues arise when these systems are used to deliver medications to
nursing units and specimens to laboratories. If a medication or patient specimen breaks
during transit, there must be a written protocol to disinfect and decontaminate the
system so that these materials do not spread within the vacuum tube delivery system or
contaminate the baskets at the end of each delivery tube.
A written decontamination protocol was developed to ensure that the vacuum pumps,
delivery tubes, shuttles, and delivery baskets would be properly decontaminated and
cleaned when there is contamination by powder or liquids in the vacuum system.
Personal Protective Equipment
Eye Protection
Glasses with side shields are the minimum acceptable eye protection in posted areas.
They are used when there is a splash hazard with small quantities of chemicals or
biological fluids, such as opening a bottle or tube, and when protection is needed from
impact with small particles. Goggles are worn when working with liquids that are caustic or
with larger volumes of hazardous chemicals or biological fluids. Face shields are worn
when working with large volumes of hazardous chemicals and biological fluids, when there
is a need to protect eyes and face, and when removing closed containers from liquid
nitrogen or other cryogenic liquids. Special eye protection such as an ultraviolet (UV)
absorbing full face shield is worn when working with transilluminators. Wavelength
specific protective eyewear is worn when working with Class 3b and Class 4 medical
Face Protection
A mask and eye protection, a face shield, or a table mounted splash shield are used to
protect mucous membranes of the eyes, nose, and mouth during all procedures and
patient-care activities that are likely to generate splashes or sprays of blood, body fluids,
secretions or excretions. This equipment is used when removing stoppers from blood
collection tubes and for all other procedures that have been associated with splashes to
the face.
Clean, non-sterile vinyl gloves are worn when touching blood, body fluids, secretions,
excretions, and contaminated items and when performing venipuncture and other
vascular procedures. Clean gloves must be put on just before touching mucous
membranes and non-intact skin. Gloves must be changed between tasks and
procedures on the same patient, and after contact with material that may contain a high
concentration of microorganisms. Gloves must be removed promptly after use, before
touching non-contaminated items and surfaces, and before going to another patient.
Gloves are changed between tasks and between procedures on the same patient if
contact occurs with contaminated material. Hands are washed promptly after removing
gloves and before leaving a patient care area.
A rear-fastening cotton gown with knitted cuffs is recommended when working at
biological safety cabinets. Gowns must be worn to protect skin and to prevent soiling of
clothing during all procedures or patient-care activities that are likely to generate
splashes or sprays of blood, body fluids, secretions, or excretions. Selection of gowns
and gown materials should be suitable for the activity and amount of body fluid likely to
be encountered. Soiled gowns must be removed promptly and hands are washed to
avoid transfer of microorganisms to other patients and environments.
Head and Foot Covers
Head and foot covers are worn to prevent soiling of clothing during all procedures that
are likely to generate splashes or sprays of blood, body fluids, secretions, or excretions.
They are also worn to reduce contamination of operating room floors (foot covers) and
the sterile field in (head cover) during surgical or clean room procedures.
NIOSH approved respirators are generally restricted to N95 negative pressure
respirators or portable powered air purifying personal HEPA respirators (PAPRs) when
entering airborne isolation rooms. N95 respirators are only used when PAPRs are not
available at Johns Hopkins Hospital. These respirators are also worn when delivering
gene therapy or drug aerosols to patients when the aerosol is not contained by
engineering controls such as a reverse flow clean air bench.
Uniforms are generally worn by healthcare personnel to protect their personal clothes or
skin. Uniforms also provide a method to identify individuals with special duties.
Biosafety Interactions with Administrative Units
The amount of biosafety staff time involved with Johns Hopkins Hospital administrative
units or departments varies with the knowledge and experience of the biosafety staff.
These interactions are also affected by the hospital safety reporting structure to the
hospital's senior administration. Safety programs that report to the medical affairs
division, as is the case at Johns Hopkins Hospital, may have responsibilities that are not
the same as safety programs that report to risk management, facilities, or human
resources. Interactions between biosafety staff and hospital units at Johns Hopkins
Hospital are briefly described below.
Clinical Engineering
Minimal interaction is needed beyond bloodborne pathogens training and development
of procedures to tag medical equipment contaminated with blood before it is repaired.
Clinical Laboratories
There is moderate interaction that is concerned with identification of environmental
microorganisms and developing proper waste management policies, including
autoclaving of cultures and modified medical waste containers to accommodate the
large volumes of glass and plastic discarded by the laboratory.
The biosafety division worked for several years with the clinical mycology section to
identify environmental fungi. This laboratory has become adept at speciating
environmental fungi, a specialty that is not available in most clinical laboratories.
Interactions are frequent because of ongoing design and construction projects,
biosafety staff certification of HEPA filter equipment, as well as assisting with
development of vendor specifications for laboratory equipment.
Minimal interaction is required other than periodic bloodborne pathogen training
because the housekeeping department is trained to handle most medical waste issues
and has a detailed procedure manual. Housekeeping maintains hospital medical waste
manifests for the six tons of hospital medical waste that is trucked to a local medical
waste incinerator every day.
Human Resources
Very little interaction is needed except for assistance with enforcement and
documentation of employee safety policies during employee annual performance
reviews and scheduling training time for new employees.
Infection Control
Frequent interaction is needed, including representation on the Infection Control
Committee due to overlap between patient and employee biosafety issues described
Legal Affairs
Moderate interaction includes monthly committee meetings and biosafety training at
physician risk management seminars.
Minimal interaction is needed because most biosafety issues are handled by self study
booklets. Biosafety, infection control, and medical divisions review the information
presented in the self study program. Biosafety programs do benefit from increased
biosafety staff participation in nursing staff training and review of work practices.
Occupational Health Services
Frequent interaction is needed because of the bloodborne pathogen and TB control
program training information and medical surveillance.
Occupational Injury Management
Heavy interaction is needed because of the bloodborne pathogen exposure hotline
activities that involve investigation of exposure incidents by the biosafety staff.
Materials Management (Purchasing)
Minimal interaction is needed except to collaborate on selection of biosafety-related
equipment and supplies to be stocked by central supply.
Biosafety Related Hospital Committees
Biosafety staff representation on hospital committees depends on each hospital's
reporting structure. Interactions with Johns Hopkins Hospital committees are briefly
outlined below.
Hospital Safety Committee
Monthly biosafety staff attendance is required
Infection Control Committee
Monthly biosafety staff attendance is required.
Protective Devices Committee
Attend when biosafety-related engineering controls, such as gloves and sharps
containers are reviewed.
Institutional Biological Safety Committee (IBC)
This committee meets when needed to review human gene therapy projects, revisions
to Biosafety Level 3 (BL-3) laboratory standard operating manuals and other research
involving human materials, goats and sheep, non-human primates and select agents.
This committee reviews all human subject protocols that have a biosafety component
and may take a direct role in training nursing staff caring for gene therapy patients,
especially those procedures involving administration of gene vectors by the respiratory
route. The hospital has inpatient clinical research units for patients enrolled in these
At large medical centers, such as Johns Hopkins Hospital, IBC activities require at least
one full time biosafety staff member to handle research registrations involving patient
material, annually updating registrations and managing a database of over one
thousand nine hundred research projects.
Institutional Review Board
Attendance is required when human subjects genetic therapy projects are discussed.
The biosafety staff review human subjects protocols that may involve bloodborne
pathogens, microorganisms, biological agents or materials and select agents.
Biosafety is one of the most rapidly expanding fields in the safety field. Control of the
transmission of microorganisms to and from hospital employees involves proper use of
administrative controls, personal protective equipment, engineering controls, and
medical surveillance. The time has come for most hospitals, especially large tertiary
care teaching hospitals, to employ staff members with a microbiology background and
knowledge of biosafety areas described in this chapter.
Attending hospital committees or workgroups that deal with employee exposure to
microorganisms is a useful way to become familiar with hospital biosafety issues.
Visiting the web sites listed in this chapter and attending national meetings hosted by
biosafety professional associations such as the American Biological Safety Association
will further enhance these experiences.
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Richard W. Gilpin, Ph.D., RBP, CBSP
Assistant Professor of Medicine
Assistant Professor of Environmental Health Sciences
Biosafety Officer
Biosafety Division, Office of Health, Safety & Environment
The Johns Hopkins Institutions
2024 East Monument Street, Room 2-700
Baltimore MD 21205-2223
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