Older studies demonstrated accelerated
rates of decline in pulmonary function
Recent longitudinal studies demonstrate
stable spirometry results
Continuing exposure to products of
Continued concern over elevated cancer
Phases of firefighting
Self-contained breathing apparatus
(SCBA): how much protection do they
Is spirometry alone adequate for medical
surveillance of firefighters?
What type of respiratory protection is
needed for firefighters during overhaul?
NIOSH recommended PF of 10,000
When inhalation rate exceeds respirator
supply, facepiece pressure will become
If there is a leak, contamination with
products of combustion may occur.
The degree of contamination will depend
on facepiece fit and extent of negative
102 of 440 firefighters were fit-tested
during fourteen shifts at eight stations.
Virtually all the firefighters present in each
station volunteered for fit-testing.
Fit-testing used a single Scott AV-2000
large facepiece and a Dynatech Nevada
CNP Fit-tests for Tucson*
Mean Leak (cc/min) All (%) Large (%)
<2.5 66 68
2.6-10 15 16
10.1-50 9 8
50.1-100 3 8
101-500 5 8
>500 4 2
*Fit-testing using a large facepiece. All refers to all firefighters tested,
large refers to firefighters fit with a large facepiece
Firefighters previously fit for personal
facepieces using irritant smoke.
Firefighters fitted with a large facepiece
were eligible for the treadmill study.
90% volunteered for testing.
Ten of the 51 eligible firefighters were
randomly selected for the treadmill tests.
Treadmill 3.5 mph and 16% gradient.
All 10 firefighters studied on the
treadmill overbreathed their respirators.
Facepiece fit was excellent in most
Only one of the 51 firefighters fit for a
large facepiece could potentially have
had a respirator PF of less than 10,000.
Seattle Fire Department since 1988
Voluntary for 1,108 uniformed firefighters
Annual pulmonary function tests including
forced vital capacity (FVC), forced
expiratory volume- 1 second (FEV1) and
diffusing capacity of the lung to carbon
DLCO by exam year
1989 1990 1991 1992 1993 1994 1995 1996
Decline in DLCO: possible causes
Changes in firefighter population (age,
race, smoking, FEV1, etc.)
Smoke exposure or other workplace
Firefighters were tested on both the regular
DLCO unit and a second similar unit
22 paired measurements were compared
No statistically significant difference was
11 of 18 firefighters with DLCO <70%
No statistically significant difference in
4 of the 11 firefighters were exercised
tested, and 3 of 4 tests were normal
-1.02 ml/min/mmHg associated with year
of measurement v. -0.006 ml/min/mmHg
associated with number of fires fought.
Actual extent of smoke exposure could not
be directly or quantitatively determined.
Is DLCO useful for medical surveillance?
Phase after the flames have been doused
when firefighters (FF) search for and
extinguish hidden sources of combustion
Usually no visible smoke
Firefighters often remove respirators
Recent study (Bolstad-Johnson et al.,
2000) suggests potential for significant
Baseline and 1 hour post-OH
FVC and FEV1
Serum Clara cell protein (CC16)
Surfactant associated protein A (SPA)
Phoenix FF wore air purifying respirators
Tucson FF wore no respiratory protection
Monitored for smoke exposure during OH
Tucson (n=25) Phoenix (n=26)
Age 39.6 ± 6.7 39.3 ± 8.1
Male gender 24 (96%) 25 (96%)
non-Hisp. White 15 (60%) 14 (54%)
Hispanic 8 (32%) 11 (42%)
Black 0 1 ( 4%)
Other 2 ( 8%) 0
Current smoker 1 ( 4%) 1 ( 4%)
Results-smoke exposure (ppm)
Analyte n* Tucson n* Phoenix
Formaldehyde 21/22 0.11±0.18 19/19 0.26 ±0.25
Acetaldehyde 5/23 0.16±0.01 18/19 0.38±0.49
0/24 11/19 6.18±7.80
Benzene 0/23 10/20 0.56±0.47
HCl 6/23 0.21±0.11 9/19 0.89±0.62
4/23 0.27±0.01 10/19 3.40±3.63
* Number of measurements exceeding LOD / number of samples collected
Measurements in mg/m3
, all other values given in ppm
Group n CC16* SP-A* n FVC (L) FEV1 (L)
TFD 25 8.9±3.5 287±144 19 5.42±0.72 4.10±0.62
TFD-OH 25 12.3±3.6†
306±157 19 5.36±0.73 3.94±0.65
PFD 26 9.6±3.5 250±117 26 5.44±0.68 4.22±0.51
PFD-OH 26 14.6±5.2†
* units µg/L
IL-10 supresses inflammation
IL-8 and TNF-α are pro-inflammatory
Relative to non-smokers, sputum IL-10
concentrations in healthy smokers are
decreased 25% and smokers with COPD
Group TNF-α IL-8 IL-10
PFD 9.8±12.4 600±795 69.2±72.5
PFD-OH 10.6±12.0 768±953 13.7±25.2*
Firefighters with rapid rates of longitudinal
decline in lung function had a 27% lower sputum
IL-10 concentration than slow decliners (p=0.59)
Phoenix FF had significant reductions in
spirometry and increase in lung
permeability following OH
OH exposures greater in Phoenix
Use of APR did not protect against
changes in biomarkers
Use self-contained breathing apparatus
Increase the time interval between
extinguishment and start of overhaul,
maximizing structure ventilation
Burgess JL and Crutchfield CD. Tucson fire fighter exposure to products of
combustion: A risk assessment. Applied Occupational and Environmental Hygiene
1995; 10: 37-42.
Burgess JL and Crutchfield CD. Quantitative respirator fit tests of Tucson fire
fighters and measurement of negative pressure excursions during exertion. Applied
Occupational and Environmental Hygiene 1995; 10: 29-36.
Burgess JL, Brodkin CA, Daniell WE, Pappas GP, Keifer MC, Stover BD, Edland
SD, Barnhart S. Longitudinal decline in measured firefighter single-breath diffusing
capacity of carbon monoxide values: A respiratory surveillance dilemma. American
Journal of Respiratory and Critical Care Medicine 1999;159:119-124.
Bolstad-Johnson DM, Burgess JL, Crutchfield CD, Storment SB, Gerkin RD.
Characterization of firefighter exposures during fire overhaul. American Industrial
Hygiene Association Journal 2000;61:636-641.
Burgess JL, Nanson CJ, Bolstad-Johnson DM, Gerkin R, Hysong TA, Lantz RC,
Sherrill DL, Crutchfield CD, Quan SF, Bernard AM, Witten ML. Adverse
respiratory effects following overhaul in firefighters. Journal of Occupational and
Environmental Medicine 2001;43:467-473.
Burgess JL, Nanson CJ, Gerkin R, Witten ML, Hysong TA, Lantz RC. Rapid
decline in sputum IL-10 concentration following occupational smoke exposure.
Inhalation Toxicology 2002;14:133-140.