Contaminated turnout gear: Testing basics and limitations
Understand the limitations of the testing process and how to work with labs to make a decision about gear
In “How to Assess Contaminated Turnout Clothing,” we explained the different types of contamination that could occur for firefighters responding to emergency events, with the primary focus on structural fires. We explained that if there were concerns about exposure to different hazardous substances, then it could be possible to test the clothing for levels of contamination to determine whether the wearing the gear posed continued exposure hazards. We suggested several questions to help make this determination.
This column provides guidance for how to answer those questions related to whether to test clothing – and whether the clothing should be considered for early retirement.
Gear contamination guidance and questions
Some aspects of a response or fire event will naturally trigger this concern. It may be the knowledge that there were certain chemicals present during an industrial facility fire. It could also be the appearance of some unusual staining or apparent degradation on the clothing after the event. In other cases, firefighters may complain after the fact about unusual rashes or other conditions when wearing the clothing. All of these circumstances can be potential clues that some form of contamination remains in the clothing.
Unfortunately, there are no universal, nondestructive test methods that can be applied to magically determine if any unusual substances are present and whether they represent a sustained hazard for use of the gear. Instead, clues must be sought out to help figure out if testing can be of value.
Ideally, knowing the substances involved in the fire is the most direct way of making this assessment for testing, as this allows testing for those specific substances. If the contamination is unknown, then the testing is likely to be much more complicated, expensive and possibly non-conclusive.
Regardless, additional information will be needed. For example, a knowledgeable individual investigating the fire will want to know whether the affected firefighters had direct contact with the chemicals, were simply operating in the area where the chemicals are present, or if the chemicals were actually on fire. Exposure can occur through a variety of different ways, including chemicals mixing with hose water runoff or being evaporated under high heat conditions.
Other important questions will include the areas of the gear where the firefighters may believe they were exposed and the amount of time they were exposed. An investigator will also want to know if there are any obvious effects on the gear, such as unusual staining or discoloration that is not thermally related. This information may be combined with any complaints by firefighters feeling effects on their skin or other health problems that may have occurred during or immediately after the fire.
Another part of the investigation will seek out information as to whether the turnout clothing was rinsed at the scene (subject to preliminary exposure reduction), how it was stored, whether it was washed and how, and the current disposition of the gear. For example, has the clothing been taken out of service, awaiting a determination for its disposition? Such questions can lead to other questions, but this is some of the fact-finding that needs to be done in order to properly assess the need for testing and whether the gear should be taken out of service.
Understanding testing limitations on firefighter gear
As noted, the type of testing to be applied will depend on the types of contaminants that might be present. While there are some generalized methods that exist, most tests for contamination are specific to different types of chemical substances. For example, entirely different procedures are used to evaluate clothing for heavy metals, such as lead or mercury, as compared to the myriad organic chemicals, such as hydrocarbons and specialty chemicals.
It is possible to do some nondestructive testing, meaning that clothing can be evaluated without cutting out pieces, but the reality is that those tests offer very limited information. One simple test involves simply rinsing a small part of the clothing and determining its pH. Clothing should have a relatively neutral pH between 6.0 and 8.0. Anything lower than 6.0 suggests some form of the acidic residue, while pH readings above 8.0 would indicate caustics. Nevertheless, measuring pH would not allow you to determine what type of acid or caustic chemical is present.
Similarly, laboratories could direct you to take wipe samples. This sampling is nothing more than taking a pre-moistened small square of material and wiping in a specific pattern over a specific area of the clothing to pick up surface contaminants. The key word here is “surface,” as this sampling does a poor job of penetrating through the individual layer that is being wiped. Chemicals can still reside inside the material layers and leach out over time, particularly as firefighters sweat inside their clothing.
The best way to evaluate clothing for contamination by testing is to actually remove (cut out) samples of the respective materials so that they can be directly extracted, with those extracts then being analyzed for the presence and amounts of specific chemicals. This, of course, means that the clothing has to be sacrificed in order to have it tested.
This comes with a further limitation that the only assessment is on the piece of clothing that is actually analyzed and makes the large assumption that the contamination found in that piece represents the rest of the clothing. In some cases, fire departments may sacrifice one or two sets to make an assessment of a much larger range of clothing that they may hope to preserve, but this again requires an assumption that whatever sacrificed sets or parts of the tested sets truly represent all the clothing being evaluated.
Even when testing is performed, there can be complications for trying to interpret and understand the test results. Most chemical analyses will show a concentration of chemical usually in milligrams or micrograms per kilogram of material or sometimes as parts per million. This information may serve to show that something is present but because there are very few known levels of permissible exposure limits for the vast majority of chemicals, it can be hard to decide whether a very small level of chemical present actually represents a hazard.
The interpretation results can be further complicated by the fact that chemical analyses of contaminated materials may show whole range of other substances being present that represent chemicals associated with finishes, dyes and body oils, which ordinarily would be found in the clothing, but tend to have complicated names and may be difficult to trace as to their origin. For this reason, is often best to test unaffected clothing, just to see with the baseline substances might be, so that anything different from the baseline in contaminated clothing samples will represent something present as a result of the fireground exposure.
Finding a lab to test firefighter turnout gear
Don’t assume that any analytical laboratory can test turnout clothing. Most commercial laboratories that do chemical analyses evaluate air, water or soil samples for different levels of different chemicals using procedure standardized from NIOSH or the EPA. These methods do not always work properly for clothing materials and often have to be adapted.
It is very important that the laboratory understands the conditions to which the clothing was subjected and specific information as discussed in the opening section of this column. For this reason, it is often best to use a forensic laboratory rather than an industrial hygiene or environmental testing laboratory. In general, laboratories will not understand protective clothing, so the fire department will need an individual who can interface with the laboratory to provide proper direction.
It is also important to realize that laboratory testing can be expensive. While relatively simple tests may run $100-$200 per sample, more exotic tests can approach $500-$600 per test. Considering the fact that multiple samples may need to be evaluated, the cost of performing testing can be prohibitive, particularly if only a few sets have been considered to be affected. For this reason, testing generally makes the most sense if it is nondestructive (not requiring the sacrifice of gear for testing purposes only) or if a fire department wishes to assess a large number of turnout clothing sets by testing just one or two clothing items. Even if an insurance company is involved, it may still be prudent to simply condemn the gear and replace it rather than performing the testing because of gear replacement costs and the uncertainty in what information testing might provide.
Overall approach to testing firefighter gear
While testing may seem to be an appropriate way to assess gear contamination, there are several factors that need to be considered. Foremost among these is the ability of the fire department to determine that the outcome of the test results will directly affect to their decisions regarding the disposition of the affected clothing. We have repeatedly discussed how cleaning does not always remove contaminants and that there are certainly some types of contaminants that are so dangerous as to warrant early retirement of the clothing without testing.
If testing is undertaken, it must be performed with the knowledge of the specific circumstances for how the gear was exposed, and with the assistance of knowledgeable persons to interpret the results as to whether any continuing risk exists for the fire department. It is also important to acknowledge that even regular structural fires and the products of combustion that contaminate clothing represent specific hazards that can remain persistent in clothing even after cleaning. Therefore, if there are lingering concerns that the clothing is unsafe and if advanced or specialized cleaning does not remove contaminants of concern, then it is the responsibility of the department to go through the appropriate steps of assessing clothing, which may require testing, or make a decision to take it out of service.
The views of the author do not necessarily reflect those of the sponsor.