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Article

Emission of Brominated Flame-Retarding Compounds from Polymeric Textile Materials Used in Firefighter Protective Garment During Thermal Exposure

by
Vincent Mokoana
1,
Joseph K. O. Asante
1,* and
Jonathan Okonkwo
2
1
Department of Physics, Tshwane University of Technology, Arcadia, Pretoria 0007, South Africa
2
Department of Environmental, Water and Earth Sciences, Tshwane University of Technology, Arcadia, Pretoria 0007, South Africa
*
Author to whom correspondence should be addressed.
Fire 2025, 8(11), 418; https://doi.org/10.3390/fire8110418
Submission received: 22 August 2025 / Revised: 2 October 2025 / Accepted: 5 October 2025 / Published: 28 October 2025
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Abstract

Firefighters wear bunker gear for protection against thermal hazards during firefighting. Bunker gear are fabricated from superior-performance fibers and enhanced by chemical flame retardants to increase fire resistance. However, brominated flame retardants (BFRs), which are widely used, have been associated with health and environmental toxicity risks. Despite the concerns, toxic BFRs continue to find application in consumer products, including in firefighter bunker gear. This study investigated the possibility of volatilization of BFRs from firefighter bunker gear during thermal exposure. Five different bunker gear samples were subjected to 3–8 kW/m2 thermal conditions in a cone calorimeter, and polyurethane foam disks were used to capture the volatilizing effluents. The samples were analyzed for brominated diphenyl ether (BDE) congeners (-28, -47, -99, -100, -154, and -209) using gas chromatography–mass spectrometry. BDE-28, -47, and -99 were detected in all five samples, with concentrations ranging from 0.02 to 0.1 ng/g, 0.03 to 0.34 ng/g and 0.18 to 0.86 ng/g, respectively. BDE-100 and -154 were detected in 80% and -209 was below the limit of detection. BDE-99 was the most abundant congener detected, followed by BDE-47. The results confirm the volatilization of BFRs from bunker gear during firefighting, which can expose firefighters to toxic flame retardants.

1. Introduction

Firefighting is a well-known profession that exposes firefighters to extreme conditions that can be described as dangerous and harmful for the general public’s health and safety. Firefighters are commonly exposed to a wide range of hazards, including open flames, extreme hot conditions, toxic smoke, and hazardous substances, such as volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs), amongst others. These occupational exposures contribute to firefighters’ higher incidence of cancers, heart diseases, and respiratory diseases than the general public [1,2,3]. In fact, 74% of firefighter deaths have been attributed to cancer caused by exposure to hazardous chemicals such as flame retardants, polycyclic aromatic hydrocarbons (PAHs), and per- and polyfluoroalkyl substances (PFAs) [2]. The firefighting occupation has been re-classified by the International Agency for Research Cancer (IARC) as ‘Group 1’ carcinogen [4]. However, there is limited information available on the real-time exposures of firefighters to hazardous substances [5].
To protect against the extreme thermal and hazardous environments encountered during fire incidents, firefighters make use of bunker gear as the first line of protection [6,7]. Bunker gear, commonly referred to as turnout gear, consists of a pair of trousers and a jacket. In the late 1980s, firefighters wore long coats and hip boots as the main protective clothing against fires [8]. Over the years, firefighters’ protective gear has been improved for better protection against the increased complexity and danger of fires. The garment is now fabricated from a combination of high-performance inherently flame-retarding textile materials such as Kevlar® and Nomex® and breathable textiles enhanced by the application of flame retardants (FRs). However, inherently flame-retardant fibers such as Kevlar®, Nomex®, and Kermel® form the backbone structure of the protective garment, particularly for the tough outer layer of the gear. The traditional firefighting bunker gear is made up of three layers, with the outer shell (outer layer) providing a tough, durable first line of defense against open flame, heat abrasion, and cuts, while the moisture barrier (middle layer) prevents water and other firefighting-related liquids from penetrating the gear and the thermal liner (inner layer) provides insulation against heat penetration [4,9,10,11]. The tough and durable outer layer is fabricated from aramid fibers (such as Kevlar® and Nomex®), polyamide, and polybenzimidazole (PBI) fibers. The moisture barrier is fabricated from highly breathable materials such as Crosstech®. The thermal liner is manufactured from materials such as Caldura® face cloth in combination with Kevlar® and Nomex®. The three bunker gear layers function together as a system to offer protection against hazardous firefighting conditions. Table 1 shows some of the common high-performance textiles used in bunker gear.
Durable textiles, including inherently flame-retardant textiles, do not require the addition of flame-retardant chemicals. These high-performance textiles can be used in combination for protection against different hazard conditions, such as the 60/40 wt % Kevlar/PBO blend. However, these textiles may be blended with chemical flame-retardant textiles to improve efficiency and comfort for the wearer as well as to reduce cost. While firefighting bunker gear is thought to have been fabricated from inherently flame-retardant materials only, a recent study reported the presence of flame retardants—particularly brominated flame retardants—in the gear [6]. Most notably, the rationale of the present study to investigate the volatilization of flame retardants from bunker gear has been informed by the results of a previous study [6]. Flame retardants are chemicals commonly incorporated into consumer products during manufacturing to enhance the flame retardancy of the materials in order to prevent and/or minimize fire hazard [1,14]. During manufacturing, flame retardants may be covalently bonded into the material (reactive flame retardant) or the surface applied to the material after production (additive flame retardant) [15]. However, the incorporation of flame retardants has been reported to result in a 15-fold increase in occupant escape time from fires [16,17,18].
At present, more than 175 flame retardants are commercially available for use in flame-retarding consumer products. Flame retardants are classified as either additive or reactive. Additive flame retardants are mostly applied to the surface and not chemically bound to the base material, while reactive flame retardants are chemically bound to the base material [14,18]. Most brominated flame retardants are additives and can leach from consumer products through their lifespan into the environment [15,19]. However, brominated flame retardants are a group of additive flame retardants widely used in a range of consumer products to maintain an adequate level of fire protection [14,20]. Polybrominated diphenyl ethers (PBDEs) are the most used BFRs to impart flame retardancy in consumer and commercial products such as textiles, plastics, and electronic casings [19]. PBDEs are commercially available in three formulations as penta-, octa-, and deca-BDE congeners. Penta-BDE congeners include BDE-28, -47, and -99; octa-BDE congeners include BDE-183, -153, and -154; and deca-BDE include BDE-209. However, the deca-BDE group of brominated flame retardants are the most widely used flame retardants in textile materials [21]. A description of some of the relevant BDE congeners is provided in Table 2.
However, brominated flame retardants—particularly polybrominated diphenyl ethers (PBDEs)—have been associated with potential health risks such as endocrine disruptions, hepatic abnormality, and cancer in human [15,20]. Furthermore, BFRs have been listed in the Stockholm Convention as persistent organic pollutants (POPs) [22,23]. Despite the restriction and ban, these potentially toxic flame retardants continue to be used commercially. Since additive flame retardants can leach out of consumer products during their lifespan, PBDEs are suspected to volatilize from the firefighter bunker gear, particularly during firefighting under thermal conditions.
Only a few studies have investigated and reported on the emission or off-gassing of contaminants from firefighter bunker gear [1,24]. The findings of a study, similar to the current study, suggest that storing firefighter bunker gear in a private vehicle that is parked in the sun could lead to the off-gassing of PBDEs [1]. The presence and subsequent emission of toxic flame retardants from the bunker gear may increase firefighters’ exposure burden. This explains, inter alia, the higher incidence of cancer reported in firefighters. This study investigated the possibility of brominated flame retardants (BFRs) volatilizing from firefighter bunker gear during thermal exposure.

2. Materials and Methods

A two-step approach was used in this study. In the first step, the bunker gear samples were exposed to simulated low-heat flux fire conditions in a cone calorimeter, and polyurethane foam (PUF) disks were closely mounted above each sample to capture any volatilizing BFR compounds that were emitted. In the second step, the PUF disks were solvent-extracted with a Soxhlet apparatus, and the extracts were analyzed for the presence of PBDEs using a gas chromatography–mass spectrometer.

2.1. Materials and Reagents

Pure individual BDE standards (BDE-28, -47, -77, -99, -100, -154, -183, and -209) were purchased from Industrial Analytica South Africa and Merck South Africa. Drierite® (calcium sulfate with cobalt chloride), used as a drying agent for the cone calorimeter, and polyurethane foam disk samplers (Whatman PUF disks) were purchased from Merck South Africa. Five different types of bunker gear material assemblies were tested. All the five selected bunker gear assembly samples had never been used (new) and were fabricated from different textile materials. These protective garments’ composition is reported in Table 3 below.

2.2. Cone Calorimeter

A cone calorimeter of the Fire Testing Technology model was used according to the International Organization of Standardization (ISO) 5660 standard [25]. The instrument was pre-set to subject each of the protective garment sample to 3–8 kW/m2 heat fluxes for a 20-min duration. The pre-selected heat flux range of 3–8 kW/m2 has been reported to correspond to the routine firefighting conditions typically faced by firefighters, with a similar exposure duration of 20 min [26,27]. The 20-min sample exposure time used in this study corresponds to the total time that firefighters can work in a structural fire while donning a self-contained breathing apparatus (SCBA). The bunker gear samples were cut into sections of 10 cm × 10 cm and covered with aluminum foil, leaving only the top part of the sample exposed. The detailed method has been described in a previous study [27]. Five different bunker garments were available for this study, and four (4) samples were taken from each bunker gear for testing, with a total of 20 samples (n = 20). The five bunker garment samples were labeled (A, B, C, D, and E), and the four samples from each gear were further assigned a number from 1 to 4 (e.g., A1, A2). The samples were tested under a laboratory ambient temperature of 25 °C and a relative humidity of 48%. When subjected to thermal conditions in the cone calorimeter, the sample materials produced smoke and heat, which were recorded as the smoke release rate (SPR) and heat release rate (HRR). This was accompanied by the samples’ loss of mass, which was recorded as the mass loss rate (MSR), signifying that the sample was degrading. The emitted compounds and soot were collected using the PUF disks mounted in the extraction hood of the cone calorimeter.

2.3. Polyurethane Foam (PUT) Disks

The Whatman EPM 2000 PUF disk samplers were sourced from Merck South Africa and used to capture volatilizing compounds. The PUF disk samplers were cylindrical in shape and measured 47 mm in diameter, with an average thickness of 0.42 mm and a pore size of 0.2 µm, and were made from borosilicate glass with a maximum temperature rating of 550 °C. In each experiment, a PUF disk was carefully placed on the stainless-steel grill mounted in the cone calorimeter’s exhaust hood. The stainless-steel grill was fixed at 130 mm above the cone heater in the extraction hood, as illustrated in Figure 1.
The stainless-steel grill PUF disk holder, shown in Figure 1, was domestically designed to suspend a disk sampler 130 mm above the cone heater and 155 mm above the radiated sample to not only capture any volatilizing compounds that were emitted but also to prevent exposure of the disk to excessive heat from the cone heater. At the end of each test, the PUF disk was removed and wrapped with two layers of the solvent-rinsed aluminum foil, placed in a Ziplock bag, and stored at −4 °C in a freezer until extraction.

2.4. Sample Preparation and Extraction

All the Whatman PUF disks were pre-cleaned using the Soxhlet extractor with hexane/acetone (2:1, v/v) for 8 h before heat exposure. After heat exposure in the cone calorimeter, the PUF disks were spiked with 10 µL of the recovery standard and extracted with approximately 250 mL of hexane/acetone (2:1, v/v) for 8 h. The same method has been described in detail elsewhere [28]. Then, the crude extracts were transferred into a round bottom flask for volume reduction to 1 mL in a 45 °C water bath using a Buchi R210 rotary evaporator supplied by Labotec (Midrand, South Africa), before being subjected to column chromatography cleaning.

2.5. Sample Clean-Up

The extracts were subjected to column chromatography cleaning in preparation for quantitative analysis with GC-MS. Pasteur pipettes (5 mm i.d × 230 mm) were packed with glass fiber, followed by 0.16 g of activated silica, 0.06 g of PestiCarb, and topped with 0.16 g of activated silica. Prior to transferring the extracts, each column was eluted with approximately 10 mL of hexane to remove impurities and to ensure that the column was saturated. Before the solvent mixture reached the bed of activated silica, a crude extract was added and eluted using 4 mL of hexane. Thereafter, the resulting eluents were concentrated under a gentle stream of nitrogen gas, using Reacti-Vap from Thermo Fisher Scientific (Bellefonte, PA, USA) as supplied by Anatech Pty (Pretoria, South Africa), to commence dryness at 45 °C. The extracts were then reconstituted in 300 µL of hexane and spiked with BDE-183 as the internal standard and vortexed. Thereafter, the extracts were transferred to 1.5 mL amber glass vials equipped with glass inserts for direct GC-MS analysis of PBDEs.

2.6. Gas Chromatography–Mass Spectrometry Analysis

The extracts were analyzed using a Shimadzu single quadrupole GCMS-QP2010SE gas chromatographer coupled to a QP 2010 ultra-mass spectrometer (Kyoto, Japan), using an electron impact ionization source, and the operation mode was set to selected ion monitoring (SIM). Sample injection into the GC was performed with a Shimadzu AOC-20i auto sampler. A capillary GC column, DB-5MS (15 m, 0.25 mm, 1.0 µm), was used with helium (99.999%, purity) as the carrier gas with flow rate of 2 mL min−1. The column’s initial oven temperature was programmed at 90 °C for 1 min, ramped up at a rate of 40 °C min−1 to 200 °C, at a rate of 25 °C min−1 to 250 °C, and then at a rate of 20 °C min−1 to 310 °C, which was held for 4 min. The splitless injection mode was used with the ion source temperature set at 250 °C and the interface temperature at 280 °C. BDE identification was conducted based on the retention times, the reference, and target ion monitoring.

2.7. Quality Assurance

The samples were analyzed using previously established laboratory QA/QC procedures. All the lab glassware were thoroughly washed with soap, rinsed with deionized water, dried in the oven over night, and then rinsed with a hexane/acetone (2:1, v/v) mixture before use. The glass wool for the packing columns was washed with the hexane/acetone (2:1, v/v) mixture and dried in the oven. Laboratory and sample blanks were used to monitor for cross-contamination and deviations. The analytical processes for PBDEs and other BFRs were conducted under ‘UV cut-off’ conditions. Good laboratory practices and measures were adhered to, including air control (i.e., fume hoods), dust control, inspection of labware measures, and QC of glassware, reference samples, standards, blanks, and column. The limit of detection (LOD) and the limit of quantitation (LOQ) were determined as three times the signal-to-noise ratio (S/N = 3:1) of the lowest calibration standard and ten times the signal-to-noise (S/N 10:1), respectively.

3. Results and Discussion

The cone calorimeter was set at low radiant heat flux to simulate the structural firefighting conditions that firefighting bunker gear is typically exposed to. During thermal exposure in the cone calorimeter, the bunker gear samples were observed to reduce in mass and produce smoke. Figure 2 illustrates the heat release rate, mass loss rate, and smoke production rate of a sample exposed to 6 kW/m2 radiant heat flux.
As shown in Figure 2a and b, respectively, the sample’s mass was observed to reduce by 0.7 g and the smoke production rate peaked at 0.0014 m2/s during the 20-min exposure period. The heat release rate in Figure 2c showed gradual increase and capped at 6 kW/m2 for the 20-min duration. The average mass loss for all the tested samples (n = 20) ranged from 0.2 g to 0.7 g. The change in mass and the production of smoke, as illustrated in Figure 2a,b, confirm the volatilization of semi-volatile organic compounds (SVOCs) from the bunker gear samples due to thermal exposure. The cone calorimeter results were used in the current study as a precursor data for the indication of possible volatilization. The preliminary confirmation of volatilization was subsequently characterized and quantified using GC-MS.
For the analysis and quantification using gas chromatography–mass spectrometry, the internal standard method was used to analyze the extracts obtained from the bunker gear samples. Extraction of analytes was performed using the Soxhlet method, and column chromatography was used to purify the extracted analytes. The extracts were analyzed for polybrominated diphenyl ethers (PBDEs) (BDE-28, -47, -99, -100, -154, and -209). 13C12 BDE-77 was used as surrogate standard to monitor the efficiency of the extraction process. The concentration levels of BDE congeners detected from the five (5) bunker gear sample types are reported in Table 4.
Of the six congeners analyzed, PBDE congeners -28, -47, and -99 were detected in all five sample materials with concentrations in the ranges of 0.02 to 0.1 ng/g, 0.03 to 0.34 ng/g, and 0.18 to 0.86 ng/g, respectively. Congeners -100 and -154 were detected in 80% of the samples. BDE-99 was the most abundant compound detected, with concentrations ranging between 0.18 and 0.86 ng/g, followed by BDE-47, with concentrations ranging from 0.03 to 0.34 ng/g. BDE-209 was below the limit of detection in almost all the bunker gear samples, except in two samples of type A, though the results were statistically insignificant. A possible explanation is that BDE-209 may not have been the flame-retarding compound of choice for use in bunker gear textiles. However, its presence was observed in a previous study that examined the levels of BDE congeners in firefighter protective clothing and thus was expected in the current study [6].
The total BDE content (∑PBDE) emitted from the samples of the five bunker gear types ranged from 0.59 to 1.25 ng/g, with type C samples having the highest content and type D samples the lowest. In previous works [6,29], where extractions were performed directly on the bunker gear (not on volatiles as in this study), the following values were found for PBDE congeners: -28 at 49.8 (0.045 µg/g); -47 at 301 (6.6 µg/g); and -99 at 12.1 (5.7 µg/g). The percentage distribution of the PBDE congeners in the five bunker gear samples varied, as depicted in Figure 3.
From Figure 3, it can be observed that BDE-99 was the most abundant congener in most of the samples, followed by BDE-47. Similar findings were reported in the studies by Alexander and Baxter [29] and Banks et al. [1]. BDE-28 was consistently present with a distribution below 10% in all bunker gear samples. There is a limited number of studies that have reported on the volatilization of PBDEs from textiles and their concentrations for a comprehensive comparison with the results of the current study. Nevertheless, Table 5 shows the levels of PBDE congeners reported in previous works in comparison with the results of the present study.
The levels of BDEs reported by the few studies shown in Table 5 are comparable with the concentration levels detected in this study [1,19,31,34]. Similarly, the study by Banks et al. [1] found that BDE-99 and -47 were the dominant contributors to the total BDE concentration, which could be attributed to the extensive usage of these congeners in consumer products, including textiles. The total BFR content detected by Banks et al. [1] was considerably higher than the level detected in the current study, possibly because of the measurements were performed after a whole-day exposure duration (24 h). In the present study, the cone colorimeter measurements were performed after only a 20-min exposure. However, the individual contents of some congeners were comparable. For example, BDE-100 and -153 were both detected in various samples with a total concentration of 0.92 and 0.72 ng/g, respectively.
Given the limited research on emissions from textiles, only a few studies could be identified [35,36]. Nevertheless, the present study hypothesized that the longer the bunker gear samples and PUF disks were exposed, the higher the concentrations of the targeted compounds. There is a need for continued research on the volatilization of flame retardants from firefighter protective gear to fully understand the exposure levels that firefighters are subjected to.

4. Conclusions

This study investigated the possible volatilization of flame retardants from firefighter bunker gear under simulated thermal conditions similar to those encountered during firefighting conditions. It was hypothesized that exposure of bunker gear textiles to elevated temperatures would induce the volatilization of flame-retarding compounds from the textile material. Five different types of bunker garments were selected, and low thermal conditions of 3–8 kW/m2 were simulated using a cone calorimeter to expose the bunker gear samples. The results of this study confirm the volatilization of PBDEs from bunker gear under thermal exposure, suggesting that firefighters are exposed to brominated flame retardants emitted from their protective garment during thermal exposure. However, no significant changes were observed with respect to BDE congener volatilization as a result of varying the heat flux from 3 to 8 kW/m2. A possible explanation is that the samples were exposed for a very short time, which was not sufficient to observe possible changes related to varying the heat flux.
Firefighting protective garments may be another source of firefighters’ exposure to brominated flame retardants given their volatilization under low thermal conditions, increasing firefighters’ exposure burdens to toxic and harmful chemicals. Firefighters’ exposure to BFRs emitted from bunker gear may be offset by taking frequent resting breaks shorter than 20 min. However, more research needs to be conducted to fully characterize the contents of flame retardants in firefighter bunker gear. Currently, there are very limited data on the volatilization of BFRs from firefighter bunker gear or from materials similar to the ones used in the fabrication of such protective gear in the literature.

Author Contributions

Conceptualization, V.M., J.O. and J.K.O.A.; methodology, V.M. and J.O.; validation, V.M., J.O. and J.K.O.A.; formal analysis, V.M. and J.O.; resources, V.M.; data curation, V.M.; writing—original draft preparation, V.M.; writing—review and editing, V.M. and J.K.O.A.; supervision, J.O. and J.K.O.A.; project administration, J.K.O.A.; funding acquisition, V.M. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Data Availability Statement

The original contributions presented in this study are included in the article. Further inquiries can be directed to the corresponding author.

Acknowledgments

M. Morethe of the Tshwane University of Technology is acknowledged for her assistance with the GC-MS measurements.

Conflicts of Interest

The authors declare no conflicts of interest.

Abbreviations

The following abbreviations are used in this manuscript:
PAHPolycyclic aromatic hydrocarbon
PFAPer- and polyfluoroalkyl substance
IARCInternational Agency for Research Cancer
FRFlame retardant
BFRBrominated flame retardant
BDEBrominated diphenyl ether
PBDEPolybrominated diphenyl ether
POPPersistent organic pollutant
PUFPolyurethane foam
FTTFire Testing Technology
SPRSmoke production rate
HRRHeat release rate
MLRMass loss rate
GC-MSGas chromatography–mass spectrometry
QA/QCQuality assurance/quality control
LODLimit of detection
SVOCSemi-volatile organic compound

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Figure 1. Suspended PUF disk at 155 mm above a heated sample.
Figure 1. Suspended PUF disk at 155 mm above a heated sample.
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Figure 2. Cone calorimeter measurements of a type E sample: (a) mass loss rate; (b) smoke production rate; and (c) heat release rate.
Figure 2. Cone calorimeter measurements of a type E sample: (a) mass loss rate; (b) smoke production rate; and (c) heat release rate.
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Figure 3. Percentage distribution of PBDE levels observed from the analyzed samples.
Figure 3. Percentage distribution of PBDE levels observed from the analyzed samples.
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Table 1. High-performance textiles used in bunker gear [12,13].
Table 1. High-performance textiles used in bunker gear [12,13].
NameTrade Name
MelamineBasofil
PolybenzimidazolePBI
Para-aramidKevlar®
Meta-aramidNormex®
Polybenzoxazole (PBO)Zylon®
Table 2. Description of BDE congeners.
Table 2. Description of BDE congeners.
Congener
Abbreviation		UIPAC NameNumber of
Bromines
1BDE-282,4,4′-Tribromodiphenyl Ether3
2BDE-472,2′,4,4′-Tetrabromodiphenyl Ether4
3BDE-773,3′,4,4′-Tetrabromodiphenyl Ether4
4BDE-992,2′,4,4′,5-Pentabromodiphenyl Ether5
5BDE-1002,2′,4,4′,6-Pentabromodiphenyl Ether5
6BDE-1542,2′,4,4′,5,6′-Hexabromodiphenyl Ether6
7BDE-1832,2′,3,4,4′,5′,6-Heptabromodiphenyl Ether7
8BDE-2092,2′,3,3′,4,4′,5,5′,6,6′-Decabromodiphenyl Ether10
Table 3. Composition of the bunker gear samples.
Table 3. Composition of the bunker gear samples.
SampleOuter ShellThermal LinerMoisture Barrier
AADVT240rsi, 39% Nomex/60% Kevlar/1% AntistaticNVL120+2L NK70N, 7.8 oz/yd2, consisting of a 50% aramid/50% viscose FR face cloth quilted to 2 layers of needle punched 80% Aramid/20% Meta Aramid batting.Diana 80AQ, 1 layer woven with a membrane (88% Nomex Comfort + Absorbent Monolithic Polyester)
BKermel® fabric (50% Kermel® + 49% Para-aramid + 1% Antistatic Yarn.Thermal barrier-Analite NP (Thermal: aramid (needle punched non-woven + Thermal liner: meta-aramid).Non-woven-Aqua Tech (The Stedair® 4000 consists of a Tri-component moisture barrier constructed using a 3.2 oz/yd2 woven DuPont & trade; Nomex® containing 2% carbon fibres, laminated to a membrane comprised of an expanded PTFE matrix combined to a continuous hydrophilic and oliophoebic polymer layer).
CAdvanced fabric (60% Kevlar® + 40% Nomex®).Thermal barrier-Analite NP (Thermal: aramid (needle punched non-woven + Thermal liner: meta-aramid).Aqua Tech (The Stedair® 4000 consists of a Tri-component moisture barrier constructed using a 3.2 oz/yd2 woven DuPont & trade; Nomex® containing 2% carbon fibres, laminated to a membrane comprised of an expanded PTFE matrix combined to a continuous hydrophilic and oliophoebic polymer layer).
DAdvanced fabric (60% Kevlar® + 40% Nomex®).Thermal barrier-Q8 (Thermal barrier: aramid (FR Rayon needle punched non-woven, thermal liner: 50% Meta Aramid + 50% FR Modacrylic).Aqua Tech (The Stedair® 4000 consists of a Tri-component moisture barrier constructed using a 3.2 oz/yd2 woven DuPont & trade; Nomex® containing 2% carbon fibres, laminated to a membrane comprised of an expanded PTFE matrix combined to a continuous hydrophilic and oliophoebic polymer layer).
EKANOX® HM02RP, >50% Para-aramidKANOX® GORNOX quilt with MAZIC® ST02 KANOXPTFE/Aramid spunlace
Table 4. Concentrations of volatilized BDE congeners (ng/g) emitted from firefighting bunker gear.
Table 4. Concentrations of volatilized BDE congeners (ng/g) emitted from firefighting bunker gear.
Target CompoundsSample ASample BSample CSample DSample E
BDE 280.04390.07500.09890.01530.0476
BDE 470.1440.3380.09310.1150.0279
BDE 990.1830.1860.6420.2960.866
BDE 100<LOD0.1120.02120.1470.0657
BDE 1540.2360.007390.3900.0150<LOD
BDE 209<LOD<LOD<LOD<LOD<LOD
<LOD means that the concentrations observed were below the limit of detection.
Table 5. Levels of BDE congeners in textiles (ng/g).
Table 5. Levels of BDE congeners in textiles (ng/g).
Sample TypeNumber of SamplesPBDE Congener∑PBDE
(ng/g)		Reference
Bunker gear (volatiles)528; 47; 99; 100; 154; 2090.59–1.25Present study
Bunker gear (off-gassing)428; 47; 99; 100; 153; 154; 183550[1]
Curtains and car interior foam828; 66; 100; 119; 153; 197; 206; 2092436.5–13,876[29]
Carpets and curtains6128; 47; 66; 100; 99; 85; 154; 153; 183; 2090.3–10[30]
Carpet, PUF and upholstery textiles1328; 47; 99; 100; 153; 154; 183; 2090.8–1.5[19]
Curtains10N/A11–120 × 106[31]
Camping tents1147; 99; 100; 154; 153; 209<0.01–7103[32]
Curtains215; 33/28/16; 47; 99; 100; 153; 154; 175/183; 2097.4–9.1[33]
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MDPI and ACS Style

Mokoana, V.; Asante, J.K.O.; Okonkwo, J. Emission of Brominated Flame-Retarding Compounds from Polymeric Textile Materials Used in Firefighter Protective Garment During Thermal Exposure. Fire 2025, 8, 418. https://doi.org/10.3390/fire8110418

AMA Style

Mokoana V, Asante JKO, Okonkwo J. Emission of Brominated Flame-Retarding Compounds from Polymeric Textile Materials Used in Firefighter Protective Garment During Thermal Exposure. Fire. 2025; 8(11):418. https://doi.org/10.3390/fire8110418

Chicago/Turabian Style

Mokoana, Vincent, Joseph K. O. Asante, and Jonathan Okonkwo. 2025. "Emission of Brominated Flame-Retarding Compounds from Polymeric Textile Materials Used in Firefighter Protective Garment During Thermal Exposure" Fire 8, no. 11: 418. https://doi.org/10.3390/fire8110418

APA Style

Mokoana, V., Asante, J. K. O., & Okonkwo, J. (2025). Emission of Brominated Flame-Retarding Compounds from Polymeric Textile Materials Used in Firefighter Protective Garment During Thermal Exposure. Fire, 8(11), 418. https://doi.org/10.3390/fire8110418

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