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43(2) 174–190
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DOI: 10.1177/1528083712450742
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Article
Studies on the properties
of nonwoven surgical
gowns
Vinay Kumar Midha, Arjun Dakuri and Varsha Midha
Abstract
Polypropylene spunbond, spunbond/meltblown/spunbond, and spunlace fabrics of 35
and 50 g/m
2
weight are tested for barrier properties against microorganisms and
liquid or body fluids to estimate their suitability for surgical gowns. The fabrics are
also treated with different levels of antibacterial and fluorochemical finishes in a single
bath using pad-dry-cure method. Liquid barrier properties of samples are analyzed by
water impact penetration, hydrostatic pressure test, and blood repellency test. Parallel
streak method is used to measure the antibacterial activity on the fabric samples with
Staphylococcus aureus. The fabric samples are also analyzed for air permeability and
stiffness. It is observed that spunbond/meltblown/spunbond fabric of 35 and 50 g/m
2
weight offer sufficient liquid barrier properties for level 2 protection as per the
Association for the Advancement of Medical Instrumentation barrier protection clas-
sification. Spunlace and spunbond fabrics of 35 and 50 g/m
2
weight offer only level 1
protection. Spunbond/meltblown/spunbond fabrics are poorest in terms of comfort,
because of their higher stiffness and lower air permeability values; spunlace fabric offers
the highest air permeability and lowest stiffness force. Spunbond/meltblown/spunbond
fabric samples with 4% and 7% fluorochemical finish and 1.5% antibacterial finish can
provide level 4 protection. Spunbond fabrics require 4% and spunbond/meltblown/
spunbond fabrics require 1% fluorochemical finish to achieve level 2 protection.
Keywords
Air permeability, antibacterial, fluorochemical, hydrostatic, nonwoven, Staphylococcus
aureus, water repellency
Dr B R Ambedkar National Institute of Technology Jalandhar, Jalandhar, India
Corresponding author:
Vinay Kumar Midha, Dr B R Ambedkar National Institute of Technology Jalandhar, GT Road Bye Pass,
Jalandhar 144011, India.
Email: midhav@gmail.com
Introduction
Surgical gowns are used by doctors and nurses as protective clothing in the oper-
ation theater to prevent the spread of bacteria from patients to surgical staff and,
therefore, reduce the incidence of hospital acquired infections [1,2]. All human
blood and other body fluids are treated as infectious to human health; act as a
carrier and transport the bacteria through the fabric, which can cause serious ill-
ness or death [3]. During surgical procedures, surgeons may be exposed to sprays of
blood or other body fluids containing pathogens. Several researchers have reported
a direct correlation between wetting by liquids and bacterial penetration of surgical
drape and gowns [4–10]. Therefore, surgical gowns address a dual function of
preventing transfer of microorganisms and body fluids from the operating staff
to the patient and also from patient to operating staff [11].
Surgical gown must repel diseases and infections yet provide adequate freedom
to move and ventilate the surgeon’s extreme body heat [12]. The first sterilized
surgical gown made from 140
s
cotton yarn was considered to be acceptable
because of its good permeability to air, softness, light weight, and comfort [13].
But it was suitable as a bacteriological barrier only in dry state. It lost its barrier
properties after becoming wet [14]. Moylan and Balish [15] reported that even in
dry conditions bacteria penetrated into the fabric irrespective of the length of the
operation procedure. Therefore, several organizations recommended on protecting
surgical staff and patients from exposure to blood borne pathogens and bacteria.
The Center for Disease Control [3] proposed that surgical gowns and drapes, either
disposable or reusable, should be impermeable to liquids and viruses and be com-
fortable to the wearer. The Association of Operating Room Nurses [16] suggested
that the fabrics used for gown and drapes must minimize passage of bacteria from
nonsterile to sterile areas and resist liquid transmission, abrasion, and punctures.
The Association of Operating Room Nurses proposed rules to minimize occupa-
tional exposure to hepatitis B virus, human immunodeficiency virus, and other
blood borne pathogens through appropriate protective clothing. The type of cloth-
ing needed depends on the occupational task and degree of exposure, e.g. liquid
resistant gowns must be worn when the surgeons become contaminated through
splashing of blood and other liquids [17]. The protective clothing should not permit
blood and other body fluids to reach or pass through surgeon’s clothes, undergar-
ments, skin, and eyes under normal condition of use and for the duration of time
for which the protective material is used [18,19]. In 1978, the Association for the
Advancement of Medical Instrumentation (AAMI) [17] established four levels of
protection on the basis of four tests, i.e. spray impact penetration, hydrostatic
head, blood repellency, and antibacterial activity tests (Table 1).
Laufman et al. tested various disposable surgical gown fabrics for bacterial
penetration of Serratia marcescens. All the fabrics made from single-layer spunlace,
a single-layer wet laid, a scrim reinforced, a fiber reinforced, and a spread tow
plastic failed in bacterial penetration during long exposures to liquid [20]. Moylan
and Kennedy and Baldwin et al.reported that nonwoven surgical materials with
Midha et al. 175
superior bacterial resistance contribute to a reduced incidence of post-operative
infections. Leonas [21] and Leonas and Jinkins [22] studied the bacterial transmis-
sion on commercially available disposable gown fabrics using Staphylococcus
aureus and Escherichia coli. The gowns were made of wood pulp/polyester spun-
laced fabrics and polypropylene spunbond/meltblown/spunbond (SMS) fabric in
single/double layers. The results showed that all fabrics resist the bacterial trans-
mission, except one of the single-layer wood pulp/polyester fabrics. Smith and
Nichols studied various types of disposable gown fabrics made from wood pulp/
polyester spunlace and polypropylene SMS. The evaluated gowns were a single-
layered fabric, reinforced fabric, and a fabric reinforced with impervious material
[13]. It was observed that gowns reinforced with impervious fabric had no liquid
penetration. All the reported studies were conducted on either liquid barrier or
bacterial transmission on different materials. None of the studies have considered
the comfort characteristics of the surgical gown materials.
In general, surgical gowns reinforced with films, coatings, or membranes meet
the standards, but these liquid proof gowns inhibit heat loss and evaporation of
sweat from the surgeon’s body making them uncomfortable during long hours of
surgical procedure. Therefore, fabric for surgical gowns and amount of liquid
resistance should be carefully selected so that the comfort properties are not
significantly compromized. Montazer and Rangchi [23] studied the effect of sim-
ultaneous antibacterial, water, and blood repellent finishes on disposable nonwo-
ven fabrics of polypropylene, polyester, and viscose, respectively. It was observed
that 1% of antibacterial fiinish was enough to produce good antibacterial
effect on the fabrics, whereas 2% fluorochemical was required to produce the
liquid repellent property. Huang and Leonas reported the optimum levels of
antibacterial and fluorochemical finishes for polypropylene SMS and a wood
pulp/polyester spunlaced nonwoven fabrics. In all the studies, the optimum
levels of antibacterial and fluorochemical finishes have been suggested for differ-
ent fabrics based on liquid barrier and antibacterial resistance. Comfort charac-
teristics of the fabrics have not been considered by the researchers in optimizing
the finishes.
Table 1. AAMI protection levels for surgical gowns.
Level Test Result
1 Spray impact penetration test (AATCC 42) 4.5 g
2 Spray impact penetration test (AATCC 42) 1g
Hydrostatic head test (AATCC 127) 20 cm
3 Spray impact penetration test (AATCC 42) 1g
Hydrostatic head test (AATCC 127) 50 cm
4 Synthetic blood test (ASTM F1670) Pass
Bacteriophage test (ASTM F1671) Pass
AAMI: Association for the Advancement of Medical Instrumentation.
176 Journal of Industrial Textiles 43(2)
In this study, suitability of spunbond, SMS, and spunlaced nonwoven fabrics of
different fabric weights (with and without fluorochemical and antibacterial finishes)
for surgical gowns has been analyzed in terms of barrier properties, air permeabil-
ity, and stiffness. Effect of different add-on levels of waterproof and antibacterial
finishes has also been studied on these properties.
Experimental
Materials
Spunbond, SMS, and spunlace nonwoven polypropylene fabrics of 35 and 50 g/m
2
weight are used in the study. Apexical waterproof 268, a slightly cationic fluoro-
chemical is used to impart the repellent properties against liquids of lower surface
tension. Zycrobial antibacterial finish, quaternary ammonium salt based com-
pound is used as antibacterial finish.
Methods
The water repellent and antibacterial finishes are applied on the same fabrics in a
single bath. Both the chemicals are miscible in a test tube after heating and stirring
for 5 min. Three add-on levels of antibacterial finish (1%, 1.5%, and 3%) are
co-applied with different levels of fluorochemical finishes (1%, 4%, and 7%) to
the nonwoven fabrics.
The most widely used method for application of chemical solution, i.e. the pad-
dry-cure process is used for the application of finishes. The fabric samples are
immersed in the bath followed by padding through squeezed rollers at a pressure
of 41.37 N/cm
2
, to remove the excess liquid. Each fabric sample is padded with the
solution twice to ensure the even distribution of solution. After padding, the fabric
is dried at 110C for 2 min and then cured at 160C for 2 min. The spunbond, SMS,
and spunlace fabrics of 35 and 50 g/m
2
weight before and after finishing are tested
for water repellency, antibacterial activity, air permeability, and stiffness. Impact
penetration test is performed according to AATCC test method 42. A
178 330 mm
2
sample with pre-weighted blotting paper is placed on an inclined
surface at an angle of 45(Figure 1).
One end of the specimen is clamped under the spring clamp at the top of inclined
stand. Another clamp of 0.4536 kg is clamped to the free end of sample. A 500 mL
of distilled water is poured in the funnel of the tester and is allowed to spray onto
the specimen from a height of 60 cm. The amount of water passing through the
fabric is given by the change in weight of the blotting paper, which is used as an
indication of water repellency of fabrics. Hydrostatic head test is performed accord-
ing to AATCC test method 127. A test specimen mounted under the orifice of a
conical well is subjected to water pressure constantly increasing at 10 0.5 cm/min
until three leakage points appear on its surface (Figure 2). The higher the column
Midha et al. 177
height achieved before appearance of third water droplet on fabric surface, higher
is the water resistance of the specimen.
The fabrics which are resistant to water may not be able to restrict the passage of
human blood during surgical procedures. Resistance of fabrics to the penetration
of synthetic blood is performed according to the ASTM F1670 test method. The
surface tension of natural blood is 0.042 N/m, whereas water has a surface tension
of 0.072 N/m. Synthetic blood is prepared from distilled water, surfactant, and red
dye. A fabric specimen of 7 7cm
2
is mounted in the test cell and a retaining screen
was placed on the sample to prevent its expansion during the test. The test cell bolts
are tightened to 13.6 Nm. The test cell chamber is filled with 60 mL of synthetic
blood and specimen is subjected to synthetic blood at the ambient condition for
5 min. The air pressure is raised to 1.38 N/cm
2
of pressure for 1 min, after that the
air pressure is released and returned to ambient condition for 54 min. The pene-
tration of synthetic blood is monitored through viewing chamber.
Parallel streak method is used to determine the antimicrobial property of the
fabric samples according to AATCC test method 147 using S. aureus, a pathogenic
gram positive bacterium. Specimens of the test material, including corresponding
Figure 1. Impact penetration for different fabric samples: (a) spunbond; (b) SMS; and (c)
spunlace.
SMS: spunbond/meltblown/spunbond.
Figure 2. Hydrostatic head test for SMS fabric sample.
SMS: spunbond/meltblown/spunbond.
178 Journal of Industrial Textiles 43(2)
untreated controls of the same material, are placed in intimate contact with growth
agar, which has been previously streaked with the test organism. After incubation,
a clear area of interrupted growth underneath and along the sides of the test
material indicates antibacterial activity of the specimen. In this test, five streaks
of S. aureus are inoculated onto nutrient agar plate approximately 60 mm in length,
spaced 10 mm apart covering the central area of petri dish without refilling the
loop. The fabric specimen of 40 mm diameter is placed in intimate contact with the
agar previously streaked with the inocula of S. aureus. The plate is incubated at a
temperature of 37C for 24 h.
Fabric weight and fabric thickness are measured according to ASTM standard
D3776 and D5736, respectively. Fabric stiffness is measured according to ASTM
standard D4032 by circular bend procedure. The circular bend procedure gives
a force value related to fabric stiffness, simultaneously averaging stiffness in all
directions. A plunger of 25.4 mm diameter forces a flat, folded swatch of fabric
through an orifice of 38.1 mm in a platform of 102 102 6mm
3
. The stroke
length of the plunger is 57 mm and the maximum force required to push the
fabric through the orifice is an indication of the fabric stiffness (resistance to
bending). The air permeability is measured as volume of airflow in cubic centi-
meters passed per second through 1 cm
2
of the fabric at a pressure of 98 N/m
2
on
Textest FX 3300-5 Air Permeability Tester. The 20 20 cm
2
specimen is clamped
on the holder in such a way that a 5 cm
2
area exposed to test is sufficiently away
from the edges in order to avoid the edge leakage. Ten readings are taken for each
sample and the average calculated. Nikon image analyzer is used to take micro-
scopic images of the fabric samples and estimate the pore size at 200 . The results
are analyzed for statistical significance at 95% confidence level.
Results and discussions
Effect of fabric weight and fabric type on water repellency
Table 2 shows the liquid barrier and antibacterial characteristics of fabric samples.
It is observed that the weight of water penetrating through the fabric during impact
penetration test decreases as the weight of fabric increases. The results are statis-
tically significant for spunbond and spunlaced fabrics at 95% confidence level.
Similarly, the hydrostatic pressure head increases with the increase in the fabric
weight for all types of fabrics. The results are statistically significant for spunbond
and spunlaced fabrics at 95% confidence level. Water repellency of fabrics increases
with the increase in fabric weight. Higher fabric weight offers more resistance to
water penetration because of higher fabric thickness (Table 3) and more number of
fibers per unit area of the fabric. More number of fibers per unit area lead to higher
entanglements and compact fabric structure, resulting in the reduction of water
penetration.
Among the fabric types, the SMS fabric shows highest water repellency, whereas
spunlace fabric shows the lowest. The results are similar for both fabric weights and
Midha et al. 179
are statistically significant at 95% confidence level. Higher surface area of the
microfibers in the meltblown-layer of SMS fabric offers finer pore size in the
layer, which acts as a liquid barrier. The spunbond fabric shows moderate
impact penetration values in both fabric weights. The bonding mechanism and
the fabric structure may be responsible for this. Thermal bonding results in melting
or fusing of fibers, thereby affecting the pores in the fabric. Spunlace fabric being
free from bonding or fusion of the filaments, offers voluminous structure with
larger pores, which is confirmed from the microscopic image of the fabrics
(Figure 3). Spunlace fabric shows pore sizes of the order of 168.87 mm, whereas
SMS fabrics show lowest pore sizes of the order of 35.27 mm (Table 2).
Table 3. Air permeability and stiffness force of nonwoven fabric samples.
S. no Sample
Fabric
thickness (mm)
Air permeability
(cm
3
/cm
2
/s)
Stiffness
force (N)
SB35 Spunbond 0.352# 373.13# 3.20#
SMS35 SMS 0.309# 75.62# 4.60#
SL35 Spunlace 0.337# 474.25# 1.00#
SB50 Spunbond 0.430# 272.63* 7.35#
SMS50 SMS 0.362# 52.15# 5.80#
SL50 Spunlace 0.471# 269.13* 2.00#
SMS: spunbond/meltblown/spunbond.
‘#’ indicates that the results are statistically significant with respect to fabric weight and fabric type at 95%
confidence level.
‘*’ indicates that the results are statistically significant with respect to fabric weight only, at 95% confidence
level.
Table 2. Liquid barrier and antibacterial characteristics of fabric samples.
S. no Sample
Fabric
weight
(g/m
2
)
Impact
penetration
(g)
Hydrostatic
head (cm)
Maximum pore
size (mm)
Antibacterial
activity
Suitability as
per AAMI
SB35 Spunbond 35 2.36# 9.00# 124.88 Fail Level 1
SMS35 SMS 35 1.00# 31.60# 37.80 Fail Level 2
SL35 Spunlace 35 4.23# 2.00# 168.87 Fail Level 1
SB50 Spunbond 50 1.96# 13.00# 90.29 Fail Level 1
SMS50 SMS 50 1.00# 38.40# 35.27 Fail Level 2
SL50 Spunlace 50 3.23# 3.40# 129.67 Fail Level 1
AAMI: Association for the Advancement of Medical Instrumentation; SMS: spunbond/meltblown/spunbond.
‘#’ indicates that the results are statistically significant with respect to fabric type and fabric weight at 95%
confidence level.
180 Journal of Industrial Textiles 43(2)
According to the AAMI barrier performance classification, the spunbond and
spunlace fabrics of 35 and 50 g/m
2
weight can be used for level 1 protection.
However, SMS fabric of 35 and 50 g/m
2
weight can be used for level 2 protection.
Effect of fabric type and fabric weight on air permeability and stiffness force
Table 3 shows the air permeability and stiffness force of the spunbond, SMS, and
spunlace fabrics of 35 and 50 g/m
2
weight.
Air permeability: It is observed that as fabric weight increases, the air permeability
decreases for all fabric types (Table 3), which is statistically significant at 95%
confidence level. Higher fabric thickness and more number of fibers per unit area
offer more resistance to air flow, leading to lower air permeability. Reduced air
permeability at higher fabric weight makes them uncomfortable.
Among the fabric types, spunlace fabrics offer highest air permeability, whereas
SMS fabrics offer the lowest air permeability for both fabric weights. The spun-
bond fabric shows moderate values of air permeability. The results are statistically
significant at 95% confidence level. Large pores due to fusion-free structure of
spunlace fabric may be responsible for its highest air permeability (Figure 3).
Thermal bonding and fusion of fibers at certain locations in spunbond fabric
makes the fabric compact, thereby reducing the air permeability. Meltblown-
layer in SMS fabric provides higher surface area of microfibers, which acts as a
barrier and is responsible for lowest air permeability. For 50 g/m
2
fabric weight, the
spunlaced fabric shows air permeability insignificantly lower than spunbond fabric,
this may due to the higher thickness of 50 g/m
2
spunlaced fabrics than 50 g/m
2
spunbond fabric (Table 3).
Fabric stiffness force: It is observed that as the fabric weight increases, stiffness force
increases for all fabric types and the results are statistically significant at 95%
confidence level. This is due to the more number of fibers per unit area and
higher fabric thickness (Table 3). Higher surface area of fibers makes the surface
compact during bonding in spunbond, SMS, and spunlace fabrics. Among the
fabric types, spunlace fabric shows lowest stiffness due to the type of bonding
Figure 3. Microscope images of 35 g/m
2
nonwoven fabrics: (a) spunbond; (b) SMS; and (c)
spunlace.
SMS: spunbond/meltblown/spunbond.
Midha et al. 181
mechanism, which is free from any fusion of fibers. SMS fabric shows highest
stiffness for 35 g/m
2
fabrics, whereas spunbond fabric shows the highest stiffness
for 50 g/m
2
. This is due to the difference in the structure of the fabrics and their
fabric thickness. The three-layer sandwiched structure of SMS fabrics bonded by
thermal bonding makes the fabric stiffer as compared to spunbond and spunlaced
fabrics, but significantly higher fabric thickness of 50 g/m
2
spunbond fabric makes
it more stiffer than SMS fabric of the same weight. Therefore, as far as the comfort
is concerned spunlace fabrics are best, whereas SMS fabrics are the poorest.
Effect of fluorochemical and antibacterial finishes on barrier properties
Water repellency: The liquid barrier properties of fabrics treated with different levels
of fluorochemical and antibacterial finishes are shown in Tables 4 and 5, respect-
ively. It is observed that the water repellency increases with the application of
fluorochemical finish for all the fabrics and the results are statistically significant
Table 4. Liquid barrier properties of 35 g/m
2
nonwoven fabrics.
S. no
Add-on level Impact penetration (g) Hydrostatic pressure (cm) Blood
repellency
Antibacterial
finish (%)
Water
repellent
finish (%) Spunbond SMS Spunlace Spunbond SMS Spunlace SMS
1 0 1 2.02 1.00# 4.09 15.80 42.10 8.40 –
2 0 4 1.00 0.97*# 3.86 21.30 50.00 9.10* Pass
3 0 7 0.96* 0.91* 3.75* 24.90 51.20* 10.90* Pass
4 1 1 2.00 0.95 4.07 16.10 42.60 9.40 –
5 1 4 0.97 0.90* 3.74 23.40 50.60 10.10* Pass
6 1 7 0.94* 0.86* 3.61* 26.10* 53.90* 12.20* Pass
7 1.5 1 1.97 0.94 4.01 16.80 44.10 10.70 –
8 1.5 4 0.96 0.90* 3.51 24.50 51.80 13.90* Pass
9 1.5 7 0.91* 0.84* 3.42* 27.00* 53.90* 15.30* Pass
10 3 1 1.17 0.92 4.01 17.80 47.10 13.30 –
11 3 4 0.95 0.89* 3.45 26.80 53.40* 14.80* Pass
12 3 7 0.93* 0.83* 3.32* 29.60* 56.00* 16.70* Pass
13 1 0 2.36# 1.00# 4.2# 9.00# 31.60# 2.00# –
14 1.5 0 2.33*# 0.99#* 4.18*# 9.10*# 31.80*# 2.00*# –
15 3 0 2.31*# 0.98#* 4.16*# 9.30*# 32.10*# 2.00*# –
16 0 0 2.36 1.00 4.23 9.00 31.60 2.00 –
SMS: spunbond/meltblown/spunbond.
‘*’ indicates that means are statistically insignificant at 95% confidence level with respect to previous add-on
level of finish.
‘#’ indicates that means are statistically insignificant at 95% confidence level with respect to unfinished fabric.
182 Journal of Industrial Textiles 43(2)
at 95% confidence level. Application of fluorochemical finish reduces the surface
energy of the fabric and does not permit the water or other fluids to adsorb and
spread on the fabric surface.
At 1% add-on of fluorochemical finish, spunbond and spunlace fabrics offer
level 1 protection as per AAMI classification, whereas SMS fabrics offer level 2
protection. As the add-on level of fluorochemical finish increases, water repellency
increases at all levels of antibacterial finish. However, the results are statistically
insignificant at 95% confidence level when add-on level increases from 4% to 7%.
Higher add-on level of fluorochemical finish reduces the surface energy by cross-
linking of fluorinated particles in the 70–100 nm range. These particles form a
durable lattice of low surface tension over the treated fabrics resulting in high
water repellency. The 4% and 7% add-on levels of fluorochemical finish increase
the protection levels for spunbond and SMS fabrics to levels 2 and 3, respectively.
Hydrostatic pressure head increases to more than 50 cm for SMS fabrics on appli-
cation of 4% and 7% flurochemical; therefore, these samples are observed for
Table 5. Liquid barrier properties of 50 g/m
2
nonwoven fabrics.
S. no
Add-on level Impact penetration (g) Hydrostatic pressure (cm) Blood
repellency
Antibacterial
finish (%)
Water
repellent
finish (%) Spunbond SMS Spunlace Spunbond SMS Spunlace SMS
1 0 1 1.25 1.00# 2.17 17.20 44.50 12.40 –
2 0 4 0.97 0.93* 1.21 25.20 50.60* 14.10* Pass
3 0 7 0.90* 0.86* 1.00* 28.50* 54.10* 16.90* Pass
4 1 1 1.23 0.91 2.07 17.40 45.20 16.40 –
5 1 4 0.95 0.83 1.11 25.80 51.80* 17.10* Pass
6 1 7 0.87* 0.80* 0.98* 28.70* 54.10* 18.20* Pass
7 1.5 1 1.18 0.90 2.14 18.30 47.10 16.70 –
8 1.5 4 0.93 0.82* 1.70 26.00 52.80* 17.90* Pass
9 1.5 7 0.83* 0.78* 1.00 30.00* 54.30* 18.60* Pass
10 3 1 1.15 0.88 1.10 25.30 47.70 17.30 –
11 3 4 0.90 0.83* 1.06* 28.30* 54.70* 18.40* Pass
12 3 7 0.81* 0.80* 0.96* 32.20* 58.60* 19.70* Pass
13 1 0 1.96# 1.00# 3.20# 13.0# 38.40# 3.40# –
14 1.5 0 1.92*# 0.99*# 3.19*# 13.2*# 38.60*# 3.60*# –
15 3 0 1.90*# 0.97*# 3.16*# 13.5*# 38.90*# 3.90*# –
16 0 0 1.96 1.00 3.23 13.00 38.40 3.40 –
SMS: spunbond/meltblown/spunbond.
‘*’ indicates that means are statistically insignificant at 95% confidence level with respect to previous add-on
level of finish.
‘#’ indicates that means are statistically insignificant at 95% confidence level with respect to unfinished fabric.
Midha et al. 183
blood repellency also. It is observed that all samples of SMS fabrics with 4% and
7% of fluorochemical finish passed the blood repellency test. These fabrics did not
permeate synthetic blood through the fabric in the test procedure of 1 h. Therefore,
SMS fabrics of 35 and 50 g/m
2
with 4% and 7% of fluorochemical finish can be
used in the critical zones of surgical gowns for level 4 protection as per AAMI
classification. Spunlace fabrics did not show any significant change in water repel-
lency after application of 4% and 7% fluorochemical finish. Therefore, spunlace
fabrics of 35 and 50 g/m
2
can provide level 1 protection as per AAMI classification
even at higher levels of fluorochemical finish.
Antibacterial activity: Table 6 shows the results of antibacterial activity on the fabric
samples at different levels of fluorochemical and antibacterial finishes. Figure 4
shows the antibacterial test on spunlaced and SMS fabric samples with different
levels of antibacterial finish. It is observed that the samples with 1% antibacterial
finish are not able to inhibit the growth of bacteria under or around the fabric.
Bacterial growth under the fabric specimen is clearly visible (Figure 4(a)). Whereas
a clear area of no bacterial growth is observed under the fabric surface for fabric
samples treated with 1.5% and 3% antibacterial finish (Figure 4(b) and (c)).
Table 6. Antibacterial activity on fabric samples.
S. no
Add-on level Antibacterial activity (35 and 50 g/m
2
)
Antibacterial
finish (%)
Water repellent
finish (%) Spunbond SMS Spunlace
10 1 – – –
20 4 – – –
30 7 – – –
41 1 – – –
51 4 – – –
61 7 – – –
7 1.5 1 Pass Pass Pass
8 1.5 4 Pass Pass Pass
9 1.5 7 Pass Pass Pass
10 3 1 Pass Pass Pass
11 3 4 Pass Pass Pass
12 3 7 Pass Pass Pass
13 1 0 – – –
14 1.5 0 Pass Pass Pass
15 3 0 Pass Pass Pass
16 0 0 – – –
SMS: spunbond/meltblown/spunbond.
‘–’ sign means the fabric sample fails the test.
184 Journal of Industrial Textiles 43(2)
Further, the effectiveness of the antibacterial finish is not influenced by the level of
fluorochemical finish.
The type of fabric does not influence the effectiveness of the antibacterial finish
necessary to achieve the antibacterial property; 1% antibacterial finish level is not
sufficient to restrict the bacterial activity on the fabric samples and 1.5% or greater
add-on levels of the antibacterial finish on all the fabrics is sufficient to inhibit the
growth of S. aureus.
Effect of fluorochemical and antibacterial treatment on air permeability and
stiffness force
Tables 7 and 8 present the air permeability and stiffness force of 35 and 50 g/m
2
fabrics, respectively.
Air permeability: It is observed that the air permeability of all fabric samples
decreases on the application of antibacterial and fluorochemical finishes. The
results are statistically significant at 95% confidence level. Increased thickness
after the application of antibacterial and fluorochemical finishes (Tables 7 and 8)
may be responsible for lower air permeability. Air permeability of fabric samples
does not show any significant change with increase in add-on level of fluorochem-
ical and antibacterial finishes.
Fabric stiffness force: Stiffness force increases with the application of fluorochemical
or antibacterial finish, which may be due to the increase in fabric thickness (Tables
7 and 8). The effect of fluorochemical finish is more on the fabric stiffness as
compared to antibacterial finish. Increase in add-on level of antibacterial and
fluorochemical finishes shows insignificant increase in stiffness for most of the
samples. The spunbond fabric samples of both fabric weight show highest fabric
stiffness at 1.5% antimicrobial finish and 7% of fluorochemical finish. The spun-
lace fabric has lowest stiffness values among all the fabrics.
Figure 4. Antibacterial test on fabric samples: (a) spunlaced fabric with 1% antibacterial finish;
(b)SMS fabric with 1.5% antibacterial finish; and (c) SMS fabric with 3% antibacterial finish.
SMS: spunbond/meltblown/spunbond.
Midha et al. 185
Table 7. Air permeability and stiffness force of 35 g/m
2
nonwoven fabrics.
S. no
Add-on level Fabric thickness (mm) Air permeability (cm
3
/cm
2
/s) Stiffness force (N)
Antibacterial
finish (%)
Water
repellent
finish (%) Spunbond SMS Spunlace Spunbond SMS Spunlace Spunbond SMS Spunlace
1 0 1 0.451 0.310# 0.393 349.87 52.41 449.60 5.15 4.70# 1.0#
2 0 4 0.454* 0.313#* 0.402* 319.7 51.63* 385.20 5.25* 4.75*# 1.1*#
3 0 7 0.472 0.322#* 0.429 311.6* 51.10* 361.70* 5.36* 4.75*# 1.1*#
4 1 1 0.388 0.309# 0.373 363.8 62.28 430.86 5.30 4.70# 1.1#
5 1 4 0.419 0.314#* 0.381* 355.13* 56.59 417.73* 5.95 4.75*# 1.1*#
6 1 7 0.429* 0.316#* 0.418* 335.3* 55.30* 408.62* 6.10* 4.80* 1.1*#
7 1.5 1 0.411 0.317# 0.370 361.57 70.61 445.00 5.70 4.70# 1.05#
8 1.5 4 0.421* 0.321#* 0.376* 327.71 66.74* 443.63* 5.80* 4.75*# 1.1*#
9 1.5 7 0.430* 0.325#* 0.378* 307.5* 65.37* 430.20* 6.20* 4.80* 1.1*#
10 3 1 0.419 0.322# 0.379 363.03 54.50 433.05 5.15 4.65# 1.1#
11 3 4 0.427* 0.327* 0.397* 356.87* 53.62* 414.16* 5.70 4.70*# 1.1*#
12 3 7 0.436* 0.335* 0.406* 339.73* 53.19* 389.72* 5.95* 4.80* 1.1*#
13 1 0 0.419 0.309# 0.361 346.43 53.06 439.60 5.45 4.65# 1.0#
14 1.5 0 0.443 0.312*# 0.388* 320.46 52.40* 385.40 5.60* 4.80* 1.0*#
15 3 0 0.451* 0.318# 0.415* 313.9* 51.53* 363.71 5.95 4.85* 1.1*#
16 0 0 0.352 0.309 0.337 373.13 75.62 474.76 3.20 4.60 1.0
SMS: spunbond/meltblown/spunbond.
‘*’ indicates that means are statistically insignificant at 95% confidence level with respect to previous add-on level of finish.
‘#’ indicates that means are statistically insignificant at 95% confidence level with respect to unfinished fabric.
186 Journal of Industrial Textiles 43(2)
Table 8. Air permeability and stiffness force of 50 g/m
2
nonwoven fabrics.
S. no
Add-on level Fabric thickness (mm) Air permeability (cm
3
/cm
2
/s) Stiffness force (N)
Antibacterial
finish (%)
Water
repellent
finish (%) Spunbond SMS Spunlace Spunbond SMS Spunlace Spunbond SMS Spunlace
1 0 1 0.491 0.372 0.526 244.90 46.17 266.30# 7.36# 5.80# 2.00#
2 0 4 0.492* 0.376* 0.553* 223.90 44.85* 247.17 8.30 6.00* 2.05*#
3 0 7 0.499* 0.381* 0.569* 218.60* 43.26* 243.70* 8.65* 6.35 2.50
4 1 1 0.432#* 0.367# 0.544 236.10 40.97 254.00 9.40 5.85*# 2.60
5 1 4 0.437*# 0.374* 0.553* 233.63* 39.21* 251.50* 9.45* 6.20* 2.60*
6 1 7 0.457 0.382* 0.577* 231.37* 37.26* 249.20* 10.30* 6.35 2.85
7 1.5 1 0.432# 0.376 0.542 230.27 45.17 244.97 11.00 5.75# 2.55
8 1.5 4 0.440*# 0.381* 0.549* 223.13* 40.62 241.77* 11.10* 6.25* 2.75*
9 1.5 7 0.465 0.394 0.565* 217.10* 38.21* 239.60* 11.85* 6.45* 2.80*
10 3 1 0.431 0.385 0.534 263.97# 42.13 242.70 11.00 5.95# 2.50
11 3 4 0.439*# 0.391* 0.543* 245.87* 39.84 240.03* 11.40* 6.45* 2.60*
12 3 7 0.451* 0.400* 0.553* 226.47* 36.43 233.40* 11.50* 6.55 2.70*
13 1 0 0.455 0.373 0.567 241.50 48.23 248.33 7.36# 5.85# 2.00#
14 1.5 0 0.463* 0.378* 0.583* 237.80* 46.58* 246.87* 7.54*# 5.97*# 2.00*#
15 3 0 0.485 0.388* 0.596* 223.60 44.21* 242.13* 8.20 6.25* 2.05*#
16 0 0 0.430 0.362 0.471 272.63 52.15 269.13 7.35 5.80 2.00
SMS: spunbond/meltblown/spunbond.
‘*’ indicates that means are statistically insignificant at 95% confidence level with respect to previous add-on level of finish.
‘#’ indicates that means are statistically insignificant at 95% confidence level with respect to unfinished fabric.
Midha et al. 187
Table 9 presents the recommended add-on levels and fabric types for different
protection levels as per AAMI classification. It is observed that level 1 protection is
provided by all spunbond, SMS, and spunlace fabrics of 35 and 50 g/m
2
. Therefore,
spunlace fabric of 35 g/m
2
is recommended for level 1 protection because of
its higher air permeability and lower stiffness force. For level 2 protection, 35
and 50 g/m
2
spunbond fabric with 4% fluorochemical finish and 35 and 50 g/m
2
SMS fabric with 1% fluorochemical finish can be used. Among these, 35 g/m
2
spunbond fabric with 4% fluorochemical finish is recommended because of its
higher air permeability as compared to SMS fabric of same weight, even though
its stiffness is slightly higher than that of SMS fabric.
For level 3 protection, 35 and 50 g/m
2
SMS fabric with 4% fluorochemical finish
can be used and its better to use 35 g/m
2
SMS fabric because of its higher air
permeability and lower stiffness than 50 g/m
2
fabric. For level 4 protection, 35
and 50 g/m
2
SMS fabrics with 4% fluorochemical and 1.5% antibacterial finish
can be used and 35 g/m
2
fabric is recommended because of its better comfort
characteristics as compared to 50 g/m
2
SMS fabric.
Conclusions
Spunbond, SMS, and spunlace nonwoven fabrics with and without application of
fluorochemical and antibacterial finishes, are studied for their suitability as surgical
gowns, in terms of water repellency, antibacterial activity, air permeability, and
stiffness force. It is observed that SMS fabric of 35 and 50 g/m
2
weight offer suf-
ficient liquid barrier properties for level 2 protections as per AAMI barrier protec-
tion classification, but are poorest in terms of air permeability and stiffness. The
protection increases to level 4 on application of 4% fluorochemical and 1.5%
antibacterial finishes. Spunlace and spunbond fabrics of 35 and 50 g/m
2
weight
offer only level 1 protection and are better in terms of air permeability and stiffness.
Spunbond fabrics provide level 2 protection on application of 4% fluorochemical
finish, whereas spunlace fabrics do not show any improvement in protection level
even after the application of fluorochemical finish. Higher add-on level of chemical
finishes results in decrease in air permeability and increase in stiffness force for all
fabric types; 1.5% add-on level of antibacterial finish is sufficient to inhibit the
growth of bacteria for all fabric types.
Table 9. Recommended surgical gown fabrics for different AAMI protection levels.
AAMI protection Surgical gown fabric
Level 1 35 g/m
2
spunlace fabric without any fluorochemical finish
Level 2 35 g/m
2
spunbond fabric with 4% fluorochemical
Level 3 35 g/m
2
SMS fabric with 4% fluorochemical
Level 4 35 g/m
2
SMS fabric with 4% fluorochemical and 1.5% antibacterial finish
AAMI: Association for the Advancement of Medical Instrumentation; SMS: spunbond/meltblown/spunbond.
188 Journal of Industrial Textiles 43(2)
Acknowledgements
The authors thank M/s Knit Foulds Pvt. Ltd Kapurthala, India, M/s Fiber Web Limited,
Daman, India, M/s Ginni filaments, Gujarat, India, M/s Apexical, Inc., Mumbai, India, and
Zydex Industries, Vadodara, India, for supplying the necessary materials for the study.
Funding
This research received no specific grant from any funding agency in the public, commercial,
or not-for-profit sectors.
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