Pak J Med Sci 2012 Vol. 28 No. 1 www.pjms.com.pk 71
Free and unobstructed airow in the upper and
lower respiratory tract during inspiration and ex-
piration is a prerequisite for normal respiratory
function. Any pathological or non-pathological
condition that can compromise free airow during
respiratory cycle can result in hypoventilation with
increased respiratory effort that can lead to physi-
ological burden involving cardiovascular
temperature regulatory system,
and can also cause
A large body of knowledge exists about possible
mechanisms and short- and long-term physiological
responses for different pathological airow limiting
conditions, involving the respiratory system endog-
enously, such as obstructive sleep apnea,
obstructive pulmonary disease and asthma.
ever, studies on physiological responses to external
airow limiting factors such as surgical and pro-
tective masks, are relatively few. Use of facemasks
of different air permeability can cause changes in
temperature and humidity in the microclimates of
the facemasks, causing different effects on heart
rate, thermal stress and perception of discomfort.
It is also shown that 1-4 hours use of surgical masks
during surgeries can result in decreased arterial
oxygen saturation levels and increased pulse rate in
1. Dr. Ahmad Alghadir, PT, PhD,
2. Dr. Farag Aly, PT, PhD,
Faculty of PT, Cairo University, Egypt.
3. Dr. Hamayun Zafar, PT, PhD,
Odontology Department, Clinical Oral Physiology,
Umea University, Sweden.
1-3: Rehabilitation Research Chair, King Saud University,
Riyadh, Saudi Arabia.
1, 3: Rehabilitation Sciences Department, CAMS,
King Saud University, Riyadh, Saudi Arabia.
Dr. Ahmad Alghadir,
Department Rehabilitation Sciences, CAMS,
King Saud University,
PO BOX 10219, Riyadh 11433, Saudi Arabia.
* Received for Publication: July 7, 2011
* Revision Received: January 2, 2012
* Revision Accepted: January 5, 2012
Effect of face veil on ventilatory function
among Saudi adult females
, Farag Aly
, Hamayun Zafar
Objective: The use of face veil called “niqab” by women to cover their faces at public places
is a common practice in some Muslim communities. The long-term effect of niqab use on
ventilatory function (VF) has not previously been reported. The aim of this cross-sectional
study was to compare VF between niqab wearing and non-niqab wearing healthy Saudi females.
Methodology: Thirty eight healthy adult Saudi females participated in this study. Nineteen
subjects were regular niqab users and the other nineteen were either not using niqab at all or
used it for less than one hour per day. Forced vital capacity (FVC), forced expiratory volume
in one second (FEV1), FEV1/FVC (%), and maximal voluntary ventilation (MVV) were recorded
using a digital spirometer.
Results: Mean values of FVC, FEV1, FEV1/FVC (%) and MVV for niqab wearers were signicantly
lower than the corresponding values for non-niqab wearers. Signicant negative correlation
was found between the FVC and FEV1 values and the number of hours of the use of face veil
Conclusions: Long-term use of traditional niqab use can affect VF.
KEY WORDS: Face veil, Ventilatory function test, Saudi, Healthy, Adult, Females.
Pak J Med Sci January - March 2012 Vol. 28 No. 1 71-74
How to cite this article:
Alghadir A, Aly F, Zafar H. Effect of face veil on ventilatory function among Saudi adult females.
Pak J Med Sci 2012;28(1):71-74
Ahmad Alghadir et al.
72 Pak J Med Sci 2012 Vol. 28 No. 1 www.pjms.com.pk
In some Muslim communities, women use face
veil called “niqab” to cover their faces at public
places. The use of niqab is more common in Arab
gulf countries, and in Saudi Arabia it is a cultural
norm and a social obligation for Saudi women to
wear niqab at public places. Due to the similarity
in which the use of facial mask and niqab can in-
terfere with the normal airow during respiration,
it can be reasonable to draw an analogy between
the use of facial masks and niqab with regard to the
physiological responses. However, to the best of
our knowledge, no previous data on physiological
impact for short- or long-term use of niqab on the VF
The spirometry data can help to study respira-
tory function and dysfunction in different condi-
tions and diseases affecting the airow in lungs
and can also provide informa-
tion about breathing reserve and exercise tolerance
to determine tness levels of healthy subjects.
spirometry, the most commonly used parameters
are vital capacity (VC), forced vital capacity (FVC),
forced expiratory volume in one second (FEV1),
and maximal voluntary ventilation (MVV). The VC
is the maximum volume of air that can be expelled
from the lungs after a maximum inspiration, FVC
is the volume of air that can forcibly be blown out
after full inspiration, FEV1 is the maximum volume
of air that can be forcibly blown out in the rst sec-
ond during the FVC manoeuvre, and MVV is the
maximum volume of air that can be inhaled and ex-
haled in one minute.
These VF values are gender
dependent with lower values in females.
We have previously shown that the parameters of
VF tests in Saudi subjects are lower than the Cauca-
sian reference values, and these gender related dif-
ferences for Saudi adults is larger than correspond-
ing differences in Caucasian population.
the analogy between the use of facial masks and
niqab with regard to the physiological responses, it
can be assumed that the long-term use of niqab can
have an impact on the VF of its user. It is hypoth-
esized that the VF values would be lower for face
veil users than non-face veil users.
The aim of this study was to compare VF values
off face veil users and non-face veil users among
healthy Saudi adult females.
Subjects: Thirty eight healthy Saudi females (aged
18-31 years; mean age 24) participated in this study.
Nineteen subjects were regular niqab users (mini-
mum of 3 years for 4 hours per day) (veil group),
and nineteen subjects were either not using niqab
at all or for less than one hour per day (non-veil
group). Users of any tobacco products and obese
subjects with body mass index (BMI) >25kg/m
were excluded. General characteristics of subjects
are shown in Table-I.
Measurements and Procedures: This study was
performed at the Cardiopulmonary Laboratory,
CAMS, King Saud University. The standing
height without shoes (cm), and weight (kg) for
calculation of BMI, and age and number of hours
of niqab use per day was noted for each subject. The
investigation was approved by the Ethics committee
of Rehabilitation Research Chair, King Saud
University. All subjects gave their informed consent
to be part of the study. The VF tests were conducted
in accordance with ‘Guidelines for Standardization
using a portable spirometer Pony
Fx (COSMED, Rome, Italy). Subjects were given
detailed information about all test procedures and
were asked to practice the test manoeuvre before the
actual test. The spirometer was calibrated daily and
tests were conducted between 9 am to 12 noon to
minimize diurnal variation,
at room temperature
C. The FVC, FEV1, and MVV were
recorded while subjects were seated comfortably in
a chair. The FEV1/FVC% was later calculated. Each
manoeuvre was performed for three to ve times
by every subject, and the largest value for each
parameter was selected.
Statistical Analysis: Mean and SD were used
for descriptive statistics. The FVC, FEV1, FEV1/
FVC (%) and MVV mean values for the face veil
group and non-face veil group were compared by
one-tail unpaired t-test with a signicance level of
Table-I: Mean, standard deviation (SD) and range of age, weight, height and BMI for healthy
face veil and non-face veil using Saudi women (n = 19, each group).
Subjects Age range Age Weight Weight(kg) Height range Height(cm) BMI range BMI
(years) (mean± SD) Range(kg) (mean± SD) (cm) (mean± SD) (kg/m2) (mean± SD)
Non-face veil 19-31 24.4 ± 2.9 51-74 58.5 ± 6.7 152-168 158.3 ± 4.8 19.4-28.5 23.3 ± 1.9
group (n= 19)
Face veil 18-31 23.7 ± 3.2 50-79 59.8 ± 7.0 149- 180 159.1 ± 6.9 19.3-27.4 24.0 ± 2.4
p -value 0.74 0.26 0.94 0.93
Pak J Med Sci 2012 Vol. 28 No. 1 www.pjms.com.pk 73
<0.05. The Pearson product moment correlation
coefcient test was used to test the presence of any
linear relationship between the number of hours of
veil use per day and the values of VF parameters.
The software SPSS version 10, was used for all
Table-II shows the mean and SD values of FVC,
FEV1, FEV1/FVC (%) and MVV for face veil and
non-face veil groups. The values for all parameters
were signicantly lower in veil group than the non-
Correlation statistics revealed signicant negative
relationship between number of hours of wearing
face veil per day and FVC (r=0.9, p-value = 0.0001)
and the FEV1(r=0.8, p-value = 0.0001), respectively.
However, correlation between number of hours
of wearing face veil per day and FEV1/FVC (%)
(r=0.215, p-value = 0.19) and MVV (r=0.188, p-value
=0.22) was not signicant.
To the best of our knowledge, this is the rst study
on the effect of niqab use on the ventilatory func-
tion. The present results show that VF values (FVC,
FEV1, FEV1/FVC (%) and MVV) for niqab wearing
females were signicantly lower than the corre-
sponding values for non-niqab wearing females. In
fact, the FVC, FEV1 and MVV values were approxi-
mately 30% lower, and the FEV1/FVC (%) was 9%
lower for niqab wearing females. The data also show
a signicant negative correlation between the dura-
tion of niqab use and the FVC and FEV1 values.
It is reasonable to believe that any condition,
pathological or otherwise, which can interfere
with the free airow in the respiratory system
or adequate expansion of lungs and chest wall,
can result in insufcient ventilation or excessive
work of respiratory muscles to maintain required
ventilation. Previous studies show that different
conditions limiting chest expansion during
respiration, such as obesity, scoliosis or use of bullet
proof vests, body armour and heavy backpacks can
reduce FVC and FEV1, without affecting the FVC/
These results indicate a proportionate
reduction in FEV1 and FVC values. However, our
present results show that FEV1/FVC% value for
niqab wearing females was signicantly lower than
the non-niqab wearing females. This indicates that
with long-term use of niqab, the FEV1 was relatively
reduced more than the FVC.
Although data on the changes in VF related to dif-
ferent pathological airow limiting conditions such
as obstructive sleep apnea,
pulmonary disease and asthma
are available, but
data on changes in VF related to non-pathological
airow limiting conditions with use of protective
masks are not available. A few previous studies on
the use of facial masks
only reported short-term
physiological responses (heart rate, thermal stress
and oxygen saturation). Thus, our present data add
new knowledge on the effect of long-term use of
niqab on VF.
It has been reported that with increased physical
activity the temperature in the facemask microcli-
causing increase in thermal sen-
sations of the whole body
, which decreases work
The temperature of air entering the
facemask during inspiration corresponds to ther-
mal stimulus to the skin under mask and affects
heat exchange from the respiratory tract, reducing
breathing comfort sensation.
Decrease in blood
oxygenation level among surgeons has also been
reported following the use of surgical masks during
surgery lasting 1 to 4 hours,
and long duration use
of facemasks by medical emergency staff has been
related to extreme stress.
Taken together, it is reasonable to believe that
the short-term physiological responses to the use of
niqab maybe similar to those previously described
for different kinds of facial masks. It can be argued
that unlike the facial masks, the niqab is usually
not very tightly applied to the face, and thus the
thermal and circulatory changes that occur when
wearing a surgical mask may not be applicable.
However, in comparison to the facial masks that
cover mainly the nose and mouth, the niqab used by
Effect of face veil on ventilatory functions
Table-II: Mean, SD and statistical comparison between mean values of different VF parameters
for healthy face veil and non-face veil using Saudi women (n = 19, each group).
Parameters Non-face veil Face veil Mean difference % of difference p-value
group (mean± SD) group (mean± SD)
FVC (litres) 3.4 ± 0.3 2.6 ± 0.4 0.8 30 % <0.001
FEV1 (litters/sec) 2.6 ± 0.5 1.9 ± 0.3 0.7 28% <0.001
FEV1/FVC (%) 80.6 ± 3.6 72.6 ± 3.1 8.0 9% <0.001
MVV (litres/min) 62.9 ± 9.0 45.6 ± 7.6 17.3 28% <0.001
FVC= Forced vital capacity, FEV1= forced expiratory volume in one second, MVV= maximal voluntary ventilation.
74 Pak J Med Sci 2012 Vol. 28 No. 1 www.pjms.com.pk
Saudi women covers the whole face except the eyes
and is thus maybe capable of causing facial mask
like short-term physiological responses. In fact, in-
creased breathing discomfort during summer is a
common complaint among our niqab wearing sub-
jects corroborating previous studies.
is available on the air and moisture permeability
of the layers of fabric used in making the niqab. It
has been reported that use of two different kinds of
facemasks with 95% and 96% ltration efciency,
can result in different mean heart rate, microclimate
temperature, humidity and skin temperature under
facemask, together with perceived discomfort, fa-
tigue and breathing resistance.
In light of these pre-
vious ndings, it is reasonable to speculate that the
present result of lower VF values in veil group than
non-veil group, is not only due to direct airway re-
sistance caused by niqab, but increase in microcli-
mate temperature, humidity and skin temperature
inside the niqab can be contributing factors. In addi-
tion, it is a possibility that part of the exhaled carbon
dioxide may also be trapped inside the niqab, lead-
ing to some shortage of oxygen causing an increase
in heart rate via sympathetic nervous system.
Furthermore, the use of niqab in presence of
known sedentary life style of Saudi females proba-
bly does not require extra respiratory effort to over-
come physiological responses to the use of niqab, as
these ladies may adapt to shallow breathing pat-
terns with higher heart rate. Prolonged reduction of
pulmonary ventilation during the use of niqab for
several hours may result in lowering the tidal vol-
ume, which may induce insufcient oxygenation
and inadequate carbon dioxide elimination. This
affects gas exchange
and thus can cause some de-
gree of hypoxia, which may lead to different mus-
culoskeletal pain disorders and reduction in endur-
ance levels. We can also speculate that the regular
use of niqab by Saudi women can probably be one
of the reasons of higher prevalence of bromyalgia
and cervicobrachialgia among Saudi females.
present results of lower VF values in veil group
than non-veil group, merit further investigations
where different physiological responses, blood oxy-
gen saturation levels and subjective perception of
discomfort should be investigated during different
levels of physical activity with niqab made of differ-
ent air and moisture permeability.
In conclusion, our data show that there are
differences in VF tests among niqab and non-niqab
wearing Saudi adult females, where values for
niqab users are lower than the values for those who
do not use niqab. Further studies are required to
investigate the effect of different fabric materials
with different air and moisture permeability that
can safely be used for niqab with minimal effect on
This study was supported by the grant from the
Rehabilitation Research Chair, King Saud Univer-
sity, Riyadh, Saudi Arabia. The authors have no
conict of interest to declare.
1. Laird IS, Goldsmith R, Pack RJ, Vitalis A. The effect on heart rate and facial
skin temperature of wearing respiratory protection at work. Ann Occup Hyg
2. Seliga R, Bhattacharya A, Succop P, Wickstrom R, Smith D, Willeke K. Effect of
work load and respirator wear on postural stability, heart rate, and perceived
exertion. Am Ind Hyg Assoc J 1991;52(10):417-22.
3. Lange JH. Health effects of respirator use at low airborne concentrations. Med
4. Morgan WP. Psychological problems associated with the wearing of industrial
respirators: a review. Am Ind Hyg Assoc J 1983;44(9):671–6.
5. Szymanowska K, Piatkowska A, Nowicka A, Cofta S, Wierzchowiecki M. Heart
rate turbulence in patients with obstructive sleep apnea syndrome. Cardiol J
6. Boulet LP, Turcotte H, Hudon C, Carrier G, Maltais F. Clinical, physiological
and radiological features of asthma with incomplete reversibility of airow
obstruction compared with those of COPD. Can Respir J 1998;5(4):270-7.
7. Li Y, Tokura H, Guo YP, Wong AS, Wong T, Chung J, et al. Effects of wearing
N95 and surgical facemasks on heart rate, thermal stress and subjective
sensations. Int Arch Occup Environ Health 2005;78(6):501-9.
8. Beder A, Buyukkocak U, Sabuncuoglu H, Keskil ZA, Keskil S. Preliminary
report on surgical mask induced deoxygenation during major surgery.
9. Hayes D Jr, Kraman SS. The physiologic basis of spirometry. Respir Care
10. Guenette JA, Witt JD, McKenzie DC, Road JD, Sheel AW. Respiratory
mechanics during exercise in endurance-trained men and women. J Physiol
11. Pierce R. Spirometry: an essential clinical measurement. Aust Fam Physician
12. Ostrowski S, Barud W. Factors inuencing lung function: are the predicted
values for spirometry reliable enough? J Physiol Pharmacol 2006;57(Suppl
13. Alghadir A, Aly F. Ventilatory function among healthy young Saudi adults: a
comparison with Caucasian reference values. Asian Biomed 2011;5(1):157-161
14. Standardization of Spirometry, 1994 Update. American Thoracic Society. Am J
Respir Crit Care Med 1995;152(3):1107-36.
15. Pellegrino R, Viegi G, Brusasco V, Crapo RO, Burgos F, Casaburi R, et al.
Interpretative strategies for lung function tests. Eur Respir J 2005;26(5):948-68.
16. Coast JR, Baronas JL, Morris C, Willeford KS. The effect of football shoulder
pads on pulmonary function. J Sports Sci Med 2005;4:367-71
17. Legg SJ. Inuence of body armour on pulmonary function. Ergonomics
18. Muza S, Latzka W, Epstein Y, Pandolf K. Load carriage induced alterations of
pulmonary function. Int J Ind Ergonomics 1989;3(3):221-27.
19. Hayashi C, Tokura H. The effects of two kinds of mask (with or without exhaust
valve) on clothing microclimates inside the mask in participants wearing
protective clothing for spraying pesticides. Int Arch Occup Environ Health
20. Nielsen R, Berglund LG, Gwosdow AR, DuBois AB. Thermal sensation of the
body as inuenced by the thermal microclimate in a face mask. Ergonomics
21. White MK, Hodous TK, Vercruyssen M. Effects of thermal environment and
chemical protective clothing on work tolerance, physiological responses, and
subjective ratings. Ergonomics 1991;349(4):445-57.
22. Meyer JP, Héry M, Herrault J, Hubert G, François D, Hecht G, et al. Field study
of subjective assessment of negative pressure half-masks. Inuence of the work
conditions on comfort and efciency. Appl Ergon 1997;28(5-6):331-8.
23. Farquharson C, Baguley K. Responding to the severe acute respiratory
syndrome (SARS) outbreak: lessons learned in a Toronto emergency
department. J Emerg Nurs 2003;29(3):222-8.
24. Ganong WF. Review of Medical Physiology. Appleton and Lange. Stamford.
25. Kaki AM. Pain clinic experience in a teaching hospital in Western, Saudi
Arabia. Relationship of patient’s age and gender to various types of pain. Saudi
Med J 2006;27(12):1882-6.
Ahmad Alghadir et al.