The one thing that settles most of it
The gradient runs inward, and it does not stop at the bunkroom door. Twenty-four Canadian stations were vacuumed and their dust analysed. Living quarters carried a median BDE-209 concentration of 7,060 ng/g. Stations whose vacuuming also took in the equipment bays and the fire truck interiors came back at 81,700 ng/g, and the authors state it plainly: "fire stations that also vacuumed equipment bays and fire truck interiors had median concentrations that were a magnitude higher (BDE-209: 81,700 ng/g) …" Peer-reviewed — Gill 2020
Silicone wristbands hung around four Ottawa stations found the same shape in a different contaminant class. Low-molecular-weight PAHs came in at a geometric mean of 442 ng/g in the vehicle bay and 348 ng/g in truck cabins, against 200 ng/g in sleeping quarters and 164 ng/g in living rooms, with every station area sitting above an office control. Peer-reviewed — Papas 2024 The bunkroom is the cleanest compartment in the building. It is still roughly 45% of the vehicle bay, and it is not an office.
One caution before the cards. A gradient is consistent with contamination migrating in from the bay, and it is equally consistent with each room having its own sources. No tracer or mass-balance study has followed a contaminant from the bay floor to the bunk. What is established is that the compounds do not all travel the same distance: across eight Queensland stations sampling engine bays, duty offices and dormitories, "polycyclic aromatic hydrocarbons were found to be transported further into fire station living environments than diesel particulate matter." Peer-reviewed — Bott 2017 A clean diesel reading in a dorm does not bound the PAH exposure there.
Real — measured, repeatedly, in three countries
Station dust is not house dust — by an order of magnitude
Vacuum-cleaner dust from 20 California fire stations gave a median BDE-209 concentration of 47,000 ng/g, against 220 ng/g for benzo[a]pyrene and 9.3 ng/g for PCB-180 in the same samples. The authors wrote that "BDE-209 concentrations in dust from California fire stations were among the highest of any previously documented homes or occupational settings in the world." Peer-reviewed — Shen 2015 Across 26 US stations in five states, the organophosphate flame retardants turned out to sit on the same order of magnitude as the brominated ones, at a maximum of 218,000 ng/g against 351,000 ng/g for PBDEs, with median TNBP, TCIPP and TDCIPP above values previously reported for homes and other workplaces worldwide. Peer-reviewed — Shen 2018
What matters: the station is not a dirtier house. Comparing 49 fire stations against 184 North Carolina homes, PFOS, PFOA, perfluorohexane sulfonate, PFNA and 6:2 diPAP were all significantly higher in station dust, while 8:2 FTOH ran higher in the homes. Peer-reviewed — Hall 2020 It is a different mixture, and it needs its own evidence.
In the Atlas: BDE-209 · TDCPP · TCPP · Tri-n-butyl phosphate · PFOS · PFOA
Real — and the bay is the dirty compartment
The gradient reaches the bunk — at roughly 45% of the bay
Two independent measurement methods agree on the shape. Dust: living quarters at a median BDE-209 of 7,060 ng/g, rising to 81,700 ng/g where the same vacuuming covered equipment bays and truck interiors, with TCIPP, TDCIPP and TPHP medians of 2,350 to 4,780 ng/g in the living quarters. Peer-reviewed — Gill 2020 Passive samplers: low-molecular-weight PAHs at 442 ng/g in the vehicle bay, 348 ng/g in truck cabins, 200 ng/g in sleeping quarters and 164 ng/g in living rooms. Peer-reviewed — Papas 2024
What matters: read the Canadian result carefully before repeating it. The 81,700 ng/g figure comes from stations whose vacuum bags also held bay and truck-cab dust, so it is a composite of the dirty compartments, not a measurement of those stations' living quarters. It bounds how much dirtier the bay is. It does not show bay dust moving into the bunkroom, and no study yet does. The wristband gradient is the separate evidence that the sleeping quarters sit above an office and below the bay.
In the Atlas: TPHP · Phenanthrene · Naphthalene · Benzo[a]pyrene
Complicated — the load is manufactured, not just deposited
Gear arrives contaminated — from the factory
In unused turnout garments the moisture barrier was a PTFE film and carried the highest total fluorine of any layer, at 122,000 mg F/kg, with targeted PFAS panels accounting for between 0.0016% and 6.7% of the total fluorine across the garment's layers. Peer-reviewed — Muensterman 2022 Ordinary wear raises what is measurable rather than wearing it off: median summed PFAS in durable-water-repellent outer shells went from 1,430 µg/kg new to 3,500 after abrasion, 4,420 after elevated temperature and 3,540 after weathering, falling to 963 µg/kg only with laundering. Regulatory — NIST TN 2260
What matters: the non-PFAS moisture barriers are not additive-free. In 12 used turnouts made between 2013 and 2024, non-ePTFE barriers held decabromodiphenyl ethane at 7,290 to 10,600 ng/cm², which the authors read as "intentional addition rather than contamination during use." Peer-reviewed — Herkert 2026 Presence is not release. No study measures what fraction of that ever reaches skin, dust or air.
In the Atlas: DBDPE · PFAS textile finishes · 8:2 FTOH
Real — where the gear sleeps changes the air
Storage is an exposure variable — and it shows in blood
Indoor air was sampled at 11 North Carolina stations plus a gear cleaning and supply facility. The finding was about rooms, not buildings: "total SVOC levels, and particularly PFAS, were significantly higher in closed rooms with turnout gear relative to storage areas open to the apparatus bay or the day room," with 8:2 FTOH reaching 1,067 ng/m³. Peer-reviewed — Stapleton 2026 Dust says the same thing. Gear locker rooms carried higher total fluorine than station living rooms at p < 0.0001, plus higher PFHxA, PFHpA and PFDoDA. Peer-reviewed — Young 2021
What matters: in 2,056 US career firefighters, turnout gear storage and transportation and carpet in the fire station living quarters were both significant predictors of serum PFAS. Peer-reviewed — Conner 2026 The furnishing of the room you sleep in on shift shows up in your blood. That is a statistical association across a large cohort, not a measured dose.
In the Atlas: PFHxA · PFHpA · 8:2 FTOH · PM2.5
Depends — a hazard identification, not a risk estimate
What the body carries — and what that does not tell you
IARC classified occupational exposure as a firefighter Group 1, carcinogenic to humans, in June 2022: sufficient evidence for mesothelioma and bladder cancer, limited evidence for colon, prostate and testicular cancer, melanoma of the skin and non-Hodgkin lymphoma. Regulatory — IARC Monographs Vol. 132 Evidence in experimental animals was rated inadequate; the classification rests on human epidemiology and human mechanistic data. In 27 Ottawa firefighters, urinary PAH metabolites rose 2.9 to 5.3-fold after a single emergency fire and urinary mutagenicity rose 4.3-fold, with PAH on skin and in personal air explaining 54% of the variance. Peer-reviewed — Keir 2017
What matters: "firefighters have more PFAS" is too coarse to be true. Against 84 office workers, 86 women firefighters were higher on PFHxS, PFUnDA and PFNA, and not on PFOA or PFOS. Peer-reviewed — Trowbridge 2020 IARC also states that a Group 1 classification does not indicate the level of cancer risk at different exposure levels. Hazard and dose are separate questions, and only one of them has an answer here.
In the Atlas: PFHxS · PFNA · 1-Hydroxypyrene · Pyrene
Complicated — tested, and mostly at the gear
What has actually been measured to work — and what has not
On-scene gross decon is real. Dish soap, water and scrubbing cut PAH contamination on turnout jackets by a median of 85%, and cleansing wipes cut PAH on neck skin by a median of 54%. In the same study, off-gassing VOC levels rose after the fire and fell 17 to 36 minutes later whether or not decon was performed. Peer-reviewed — Fent 2017 Washing PPE removed on average 61% of PAHs and 55% of antimony, alongside 97% of lead and 90% of cadmium. Peer-reviewed — Keir 2020
Laundering is where the picture breaks. On real uniforms after live burns, a significant reduction in the sum of 13 PAHs appeared in only 3 of 16 sampled areas, with no significant change in 6 organophosphate flame retardants or 7 PBDEs. Peer-reviewed — Banks 2021 On fabric swatches, a 12-hour pre-soak at a 90:10 water-to-detergent ratio removed 97% of low-molecular-weight and 78% of high-molecular-weight PAHs, against 11% at 99:1. Peer-reviewed — Hossain 2024 Nobody has run the high-detergent protocol on real gear with field contamination. Worse, washing moves bromine around: PBDEs averaged 43% higher in routinely laundered hoods, and unexposed hoods washed alongside contaminated ones came out with more. Peer-reviewed — Mayer 2019
What matters: one intervention in this entire field has a randomised trial behind it, and it is donating blood. Over 52 weeks in 285 Fire Rescue Victoria staff, plasma donation every six weeks lowered mean serum PFOS by 2.9 ng/mL and PFHxS by 1.1 ng/mL, blood donation every 12 weeks lowered PFOS by 1.1 ng/mL, and the observation arm did not change. Peer-reviewed — Gasiorowski 2022 The authors say the clinical implications still need evaluating. Meanwhile, of 31,281 firefighters in a 2021 records database, 82% of those documenting a fire exposure performed at least one decon procedure and 5% documented the full best-practice set. Peer-reviewed — Fernandez 2023 Adherence is the binding constraint, not efficacy.
What reduces it, per compound: the Exposure Ledger
What nobody has measured
The bed. In every study located for this page, "sleeping quarters" means room air, floor dust, or a passive sampler hung in the room. There is no published measurement of a fire station mattress, pillow, mattress cover or bunk surface for PAHs, PBDEs, organophosphate esters or PFAS. Fifteen years of work has characterised the apparatus bay floor, the truck cab, the jacket, the hood, the gloves and the wrist. The surface a body is in continuous contact with for a third of the shift has never been sampled once.
Most of the fluorine has no name. In fire station dust, the 24 targeted PFAS accounted for "less than 2% of fluorine in dust (n = 39), suggesting the potential presence of unknown PFAS." Peer-reviewed — Young 2021 Over 98% of the fluorinated burden in the building carries no compound name, no CAS number and no toxicology.
No dose. Every number on this page is a concentration: ng/g in dust, ng/g on a wristband, ng/m³ in air. None has been converted to an inhaled or dermally absorbed dose across a sleep period, and no inhalation reference concentration exists for BDE-209, TDCIPP, TCIPP or the fluorotelomer alcohols to judge a bunkroom measurement against. That absence is what The Dose Gap was built to count. The single exception here is narrow: the North Carolina air study modelled a PFOA risk from inhaled 8:2 FTOH in gear storage rooms, not in bunkrooms.
No intervention has been tested at the bunk. There is no published before-and-after study of hot-zone/cold-zone station design, dedicated gear-room exhaust, bay-door interlocks or bunkroom air filtration measured against contaminant levels where people sleep. The station-design recommendation currently rests on one cross-sectional air survey of 11 stations in one state over one summer.
And no measurement past the front door. Not one published study has measured chemical contamination inside a firefighter's own home, sampled a personal commuter vehicle, or biomonitored a spouse or child. The route is documented up to the driveway: a laundered uniform in an enclosed private vehicle off-gassed 13 PAHs at 7,800 to 23,000 ng per uniform per day. Peer-reviewed — Banks 2021b Compare what the other take-home literatures did. Lead was detected on 46 (58%) of the home surface wipes taken in lead-exposed construction workers' households, highest in the kitchen, then the entrance, the living room, the bedroom and the laundry room. Peer-reviewed — Ceballos 2026 Orchard workers' commuter vehicle dust and house dust were quantitatively linked at R² = 0.44. Peer-reviewed — Fenske 2013 The one firefighter-to-family measurement that exists is a null: baseline PBDE concentrations and AhR responses in breastmilk did not differ between 21 firefighters and 10 non-firefighters, and did not change after a structural fire. Peer-reviewed — Jung 2023 Small sample, narrow analyte set, and the only thing anyone has looked at.
One loose end we will not tidy. A NIOSH health hazard evaluation of three fire stations is reported to have found no evidence of diesel exhaust moving from the apparatus bay into the living and sleeping quarters, which would cut against the migration reading of the gradient above. We could not retrieve that document, so we are neither quoting it nor discounting it, and it stays out of the citation list below until somebody opens it.
Where this sits
A fire hall is a bedroom with a diesel engine in it, and it is the best-characterised bedroom in the world right up to the point where the bed starts. The settled chemistry of ordinary homes is covered in what's in your house dust, the airborne half in your indoor air, and the room this site exists for in your bedroom. The compounds named on this page each have a cited page in the Atlas, and the public datasets joined against them are open and downloadable in the Exposure Ledger.
The reason to say all of this out loud rather than quietly is that the missing measurement is cheap. Somebody with a wipe kit, a research protocol and access to a bunkroom could close the largest gap on this page in a weekend. Until then, presence is not dose, and the bunk is a blank.