Mark Mendell

• Lawrence Berkeley National Laboratory

This research assesses benefits of adding to California Title-24 ventilation rate (VR) standards a performance-based option, similar to the American Society of Heating, Refrigerating, and Air Conditioning Engineers “Indoor Air Quality Procedure” (IAQP) for retail spaces. Ventilation rates and concentrations of contaminants of concern (CoC) were mea...

In developing evidence-based, health-protective guidelines for indoor dampness/mold, one goal is to quantify the health risks from indoor dampness. A first step is to synthesize existing epidemiologic findings on measured home moisture and health. Findings were combined from the only two published studies assessing associations between measured wal...

Moisture measurements in the homes of participants in a birth-cohort study were evaluated for possible differences between readings on living room and bedroom walls, readings in homes with and without qualitative indications of dampness or disrepair (i.e., visible mold, visible water damage, a musty or moldy odor, or peeling paint), and readings on...

While current evidence suggests that prevention and remediation of indoor dampness and dampness-related agents are likely to reduce health risks, evidence is not yet available to support quantitative guideline levels for specific indoor microbiologic concentrations. This paper recommends approaches for developing evidence to support quantitative he...

Building dampness has many causes and is among the most pervasive and persistent indoor environmental concerns. A glove box enclosure was evaluated for its suitability as a test environment to determine the moisture content of building materials, gravimetrically and with various field instruments, after conditioning the materials to different humid...

Unlabelled: Dampness and visible mold in homes are associated with asthma development, but causal mechanisms remain unclear. The goal of this research was to explore associations among measured dampness, fungal exposure, and childhood asthma development without the bias of culture-based microbial analysis. In the low-income, Latino CHAMACOS birth...

Limited evidence associates inadequate classroom ventilation rates (VRs) with increased illness absence (IA). We investigated relationships between VRs and IA in California elementary schools over two school years in 162 3(rd) -5(th) grade classrooms in 28 schools in three school districts: South Coast (SC), Bay Area (BA), and Central Valley (CV)....

A study was conducted to investigate the possibility of CO2 emerging as a potential source of indoor pollution. It was observed that the magnitude of the indoor-outdoor difference in CO2 concentration increased, as the outdoor air ventilation rate per person decreases resulting in indoor pollution. The results from the study stimulated efforts to e...

Many studies have shown consistent associations between evident indoor dampness or mold and respiratory or allergic health effects, but causal links remain unclear. Findings on measured microbiologic factors have received little review. We conducted an updated, comprehensive review on these topics. We reviewed eligible peer-reviewed epidemiologic s...

The commercial building ventilation standard (62.1-2010) of the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) contains alternate procedures: the prescriptive Ventilation Rate Procedure (VRP) and the rarely used Indoor Air Quality Procedure (IAQP). The IAQP allows lower ventilation rates (VRs) than the VRP, if ad...

Dampness and mold have been shown in qualitative reviews to be associated with a variety of adverse respiratory health effects, including respiratory tract infections. Several published meta-analyses have provided quantitative summaries for some of these associations, but not for respiratory infections. Demonstrating a causal relationship between d...

Abstract Abstract Some prior research in office buildings has associated higher indoor temperatures even within the recommended thermal comfort range with increased worker symptoms. We reexamined this relationship in data from 95 office buildings in the US Environmental Protection Agency’s Building Assessment Survey and Evaluation Study. We invest...

Abstract Abstract Data from published studies were combined and analyzed to develop best-fit equations and curves quantifying the change in sick building syndrome (SBS) symptom prevalence in office workers with ventilation rate. For each study, slopes were calculated, representing the fractional change in SBS symptom prevalence per unit change in...

Abstract Abstract Building-related symptoms in office workers worldwide are common, but of uncertain etiology. One cause may be contaminants related to characteristics of heating, ventilating, and air-conditioning (HVAC) systems. We analyzed data from 97 representative air-conditioned US office buildings in the Building Assessment and Survey Evalu...

Abstract Abstract Used ventilation air filters have been shown to reduce indoor environmental quality and worker performance and increase symptoms, with effects stronger after reaction of filters with ozone. We analyzed data from the US EPA Building Assessment Survey and Evaluation (BASE) study to determine if ozone and specific filter media have...

Unlabelled: Reactions between ozone and indoor contaminants may influence human health and indoor air quality. The U.S. EPA Building Assessment Survey and Evaluation (BASE) study data were analyzed for associations between ambient ozone concentrations and building-related symptom (BRS) prevalence. Multiple logistic regression (MLR) models, adjuste...

Nonspecific building-related symptoms among occupants of modern office buildings worldwide are common and may be associated with important reductions in work performance, but their etiology remains uncertain. Most reported research into environmental risk factors for these symptoms has focused on ventilation system-related factors, dampness, and pa...

Abstract Abstract Most research into effects of residential exposures on respiratory health has focused on allergens, moisture/mold, endotoxin, or combustion products. A growing body of research from outside the US; however, has associated chemical emissions from common indoor materials with risk of asthma, allergies, and pulmonary infections. Thi...

Unlabelled: The Institute of Medicine (IOM) of the National Academy of Sciences recently completed a critical review of the scientific literature pertaining to the association of indoor dampness and mold contamination with adverse health effects. In this paper, we report the results of quantitative meta-analyses of the studies reviewed in the IOM...

Regents of the University of California. The submitted manuscript has been authored by a contractor of the US Government under contract No. DE‐AC03‐76SF00098. Accordingly, the US Government retains a nonexclusive, royalty‐free license to publish or reproduce the published form of this contribution, or allow others to do so, for US Government purpos...

We assessed associations between indicators for moisture in office buildings and weekly, building-related lower respiratory and mucous membrane symptoms in office workers, using the U.S. EPA BASE data, collected in a representative sample of 100 U.S. office buildings. We estimated the strength of associations between the symptom outcomes and moistu...

This paper summarizes three analyses of data on building-related environmental factors and occupant symptoms collected from 100 representative large U.S. office buildings. Using multivariate logistic regression models, we found increased occupant symptoms associated with a number of building-related factors, including lower ventilation rates even a...

Purpose The goal of this project was to develop, based on the experience of those who investigate health complaints in buildings, practical strategies for preventing building-related symptoms in office buildings, suitable for use by those who own, lease, or manage office space. Methodology/approach Ideas from six experienced building investigators...

The Institute of Medicine (IOM) of the National Academy of Sciences recently completed a critical review of the scientific literature pertaining to the association of indoor dampness and mold contamination with adverse health effects. In this paper, we report the results of quantitative meta-analysis of the studies reviewed in the IOM report. We de...

Unlabelled: To assess whether school environments can adversely affect academic performance, we review scientific evidence relating indoor pollutants and thermal conditions, in schools or other indoor environments, to human performance or attendance. We critically review evidence for direct associations between these aspects of indoor environmenta...

Insufficient information has been available on measured ventilation rates and symptoms in office workers. using US EPA data from 100 large US office buildings, they assessed relationships in multivariate models between ventilation/person and lower respiratory and mucous membrane symptoms. Three preliminary ventilation estimates were used, based on...

In this issue of the journal, Preziosi et al. [2004] report the first study to assess differences in the utilization of health care related to the presence of air-conditioning in office workplaces. Although the study was simple and cross-sectional, the data variables from questionnaires, and the findings subject to a variety of questions, the findi...

We evaluated relationships between lower respiratory symptoms and risk factors for microbiological contamination in office buildings. The National Institute for Occupational Safety and Health collected data from 80 office buildings during standardized indoor environmental health hazard evaluations. Present analyses included lower respiratory sympto...

Indoor nonindustrial work environments were designated a priority research area through the nationwide stakeholder process that created the National Occupational Research Agenda. A multidisciplinary research team used member consensus and quantitative estimates, with extensive external review, to develop a specific research agenda. The team outline...

A summary is given based on surveys including 2,435 workers in 80 office buildings, of the associations between HVAC design and maintenance characteristics or building maintenance characteristics and work-related lower respiratory symptoms, allergic symptoms, and asthma development. The statistical models determined the strength and statistical unc...

We studied the effects of removing small airborne particles in an office building without unusual contaminant sources or occupant complaints. We conducted a double-blind crossover study of enhanced particle filtration in an office building in the Midwest United States in 1993. We replaced standard particle filters, in separate ventilation systems o...

During parts of 7 consecutive weeks, indoor and outdoor particle number concentrations and particle sizes were measured versus time in a large sealed air-conditioned office building without tobacco smoking. Building ventilation rates were also measured. During some periods, the normal filters in the building’s air handling systems were replaced wit...

Air and dust samples were collected on two floors of an office building during a double-blind particle intervention study to examine spatial and temporal variability of airborne endotoxin over a period of weeks, and to characterize endotoxin activity and lipopolysaccharide (LPS) content in carpet and chair dust. Air samples were collected on multip...

This paper reviews current literature on the associations of ventilation rates and carbon dioxide concentrations in non-residential and non-industrial buildings (primarily offices) with health and other human outcomes. Twenty studies, with close to 30,000 subjects, investigated the association of ventilation rates with human responses, and 21 studi...

A pilot study was conducted on thirty office workers to help determine if a scannable form of symptom severity questions would yield similar results as a nonscannable form. There were three goals of the pilot study: first, to observe if, in a questionnaire using two forms of Visual Analog Scares (VAS), questions using a scannable sequence of "boxes...

Abstract Occupants of office buildings are exposed to low concentrations of complex mixtures of volatile organic compounds (VOCs) that encompass a number of chemical classes and a broad range of irritancies. “Sick building syndrome” (SBS) is suspected to be related to these exposures. Using data from 22 office areas in 12 California buildings, seve...

Workers in indoor environments often complain of symptoms, such as eye and nose irritation, headache, and fatigue, which improve away from work. Exposures causing such complaints, sometimes referred to as sick building syndrome, generally have not been identified. Evidence suggests these worker symptoms are related to chemical, microbiological, phy...

The California Healthy Building Study was designed to assess relations between ventilation system type and office worker symptoms in a set of U.S. buildings selected without regard to worker complaints. Twelve public office buildings in northern California meeting specific eligibility criteria were studied in the summer of 1990: three naturally ven...

Associations between environmental factors and work-related health conditions were assessed using regression techniques with environmental and health data for 2435 respondents in 80 office buildings included in the National Institute for Occupational Safety and Health Health Hazard Evaluation program. The health conditions analyzed included two sym...

The National Institute for Occupational Safety and Health (NIOSH) conducted four seasonal surveys in 1992 at a General Services Administration (GSA) building in Overland, Missouri, using a standard instrument to collect symptom information from occupants. The GSA building, first occupied in 1991, serves as a Federal Records Center, houses 1800 to 2...

Concentrations of total volatile organic compounds (TVOC) and of 39 individual volatile organic compounds (VOCs) were measured in 12 northern California office buildings of three different ventilation types. The objectives were to characterize indoor air exposures to VOCs, to investigate variations in chemical composition and concentrations among t...

The primary goal of the California Healthy Building Study (CHBS) is to identify the major characteristics of buildings, ventilation systems, jobs, and indoor environmental quality that are associated with building-related sick-building health symptoms. The first phase of the CHBS was a cross sectional study of 12 office buildings located in the San...

Twelve public office buildings were selected for a study of relationships between worker's health symptoms and a number of building, workspace, job, and personal factors. Three buildings were naturally ventilated, three were mechanically ventilated, and six were air conditioned. Information on the prevalences of work-related symptoms, demographics,...

The California Healthy Building Study (CHBS) is a multidisciplinary research based in 12 office buildings within California. The overall goal the CHBS is to elucidate relationships between occurrences of office worker health symptoms and characteristics of the workers` buildings, ventilation systems, work spaces, jobs, and indoor environments. A Ph...

Published studies of the relation between type of building ventilation system and work-related symptom prevalence in office workers have been contradictory. A reanalysis was performed of six studies meeting specific eligibility criteria, combining published data with unpublished information obtained from study authors. Five eligible studies were fr...

A computerized database of 93 California State Superfund waste sites was created to assess the feasibility of using such a system for a variety of public health purposes. Though available data were limited in many respects, analysis of the database proved useful in summarizing features of hazardous waste sites that could be of considerable public h...

Metrics of culturable airborne microorganisms for either total organisms or suspected harmful subgroups have generally not been associated with symptoms among building occupants. However, the visible presence of moisture damage or mold in residences and other buildings has consistently been associated with respiratory symptoms and other health effe...

Data from published studies were combined and analyzed to develop best-fit equations and curves quantifying the change in sick building syndrome (SBS) symptom prevalence with ventilation rate. For each study, slopes were calculated, representing the fractional change in SBS symptom prevalence per unit change in ventilation rate per person. Values o...

We developed and pilot-tested an overall protocol for intervention studies to evaluate the effects of indoor environmental changes in office buildings on the health symptoms and comfort of occupants. The protocol includes a web-based survey to assess the occupant's responses, as well as specific features of study design and analysis. The pilot stud...

The paper presents a summary of a review [1] of current literature on the associations of ventilation rates in non-residential and non-industrial buildings (primarily offices) with health and other human outcomes. Twenty studies, with close to 30,000 subjects, investigated the association of ventilation rates with human responses. (Twenty one studi...

The California Healthy Building Pilot Study was conducted in 12 office buildings in two climate zones in the San Francisco Bay area, was designed to test several hypotheses concerning the relationships between type of building ventilation, air quality, thermal comfort and occupant symptoms. The primary objectives of the study were (1) to determine...