Turnout gear service life: Will we ever have clear 'keep or retire' guidelines?
Determining what gear can be reasonably expected to survive and for how long is still subject to interpretation
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There has been an ongoing debate ever since the original requirement for mandatory retirement of turnout clothing took effect with the 2008 edition of NFPA 1851: Standard on Selection, Care, and Maintenance of Protective Ensembles for Structural Fire Fighting and Proximity Fire Fighting. Many in the fire service found this requirement to be overbearing and without substantiation. They questioned the need for such a requirement, particularly when some structural gear may be subjected to very little use or has shown no evidence of serious damage even after 10 years. (Read our previous comments on the debate here.)
The committee responsible for this requirement, which remains in effect through the 2020 edition of NFPA 1851, substantiates the need for changing out structural turnout clothing every 10 years for several reasons:
- Significant changes in the protection technology occur in the 10-year period that has been linked to two 5-year revision cycles in NFPA 1971 for updating design and performance of turnout gear;
- The inability to accurately assess gear performance where degradation in protection may not be visible; and
- The accumulation of increasing amounts of contamination in gear over its use in structural fires that may not be removed by regular laundering.
While we don’t seek to resolve this debate here, we will offer a better understanding of what constitutes the usable service life of turnout gear.
What is gear service life?
The service life of any product is intended to represent how long that product remains viable and fit for use. It is generally defined by several years or months. Service life is based on the product being delivered in a new condition and cared for and maintained in accordance with manufacturer’s instructions that include acceptable procedures for cleaning, repair and storage. This does not mean that the gear may not be ruined in use if subjected to severe exposures or rugged environments.
Structural firefighting involves ever-changing response environments and conditions, so the determination of what gear can be expected to survive is subject to interpretation. Even new gear can be exposed to extreme fireground temperatures that cause significant damage to render it unusable or unrepairable. Gear could also be contaminated to the point where cleaning and decontamination do not bring the gear back to a usable condition. Therefore, the actual service life for gear can be from its first use to whatever indicated period of time the department judges the gear as still being protective based on the results of Advanced Inspection performed according to NFPA 1851.
Service life differs from shelf life in that shelf life applies to gear that is not used but instead properly stored. Shelf life is akin to an expiration date where certain materials or components may break down due to environmental conditions like ozone exposure or natural deterioration over time.
Service life is also not related to manufacturer warranties. Warranties represent decisions made by manufacturers usually in terms of their manufacturing quality and what they consider reasonable continued usability subject to a number of caveats.
How are gear performance criteria set?
Critical to the service life discussion is the expectation that the gear will continue to provide protection at the necessary levels of performance. Key performance criteria include protection against clothing ignition and heat degradation in addition to thermal insulation and resistance to physical hazards. There is a wide range of other properties that define protection from hazardous liquids like blood and fireground chemicals that are balanced by the impact of the clothing on the wearer causing heat stress. The committee chooses test methods that are applied to individual materials and composites. The minimum results for these test methods are then set based on how different products perform in the field and are generally correlated with clothing that demonstrates acceptable field protection. The process for how these criteria is set often involves consideration of several factors and can be relatively complex. Nonetheless, collectively these criteria form the basis of minimum performance for gear when new.
It is important to recognize that performance criteria in the NFPA 1971 standard applies to clothing samples that are not worn. Even when samples may be exposed to various conditions like multiple launderings or low-level heat exposures, these preconditions cannot fully replicate the kind of impacts that actual wearing will create on clothing. Consequently, it is important to realize that applying NFPA 1971 criteria to used clothing can be complicated and can misrepresent the intended use of those requirements. This is because some performance criteria can be set higher than needed to account for the fact that the clothing performance can partially diminish in use and still provide a reasonable level of protection.
How does gear performance change from exposure?
We know from experience that certain conditions of use and exposures can break down and reduce performance. Perhaps two of the most common examples are the inappropriate use of bleach on certain fabrics during cleaning and direct exposure to ultraviolet light. Excessive exposure to either of these conditions can radically reduce the strength of the fabrics to the degree that they will hand tear. Of course, proper cleaning and storage of gear can avoid degradation from these conditions. However, clothing is also subject to abrasion, various other physical hazards, high-heat exposures, and contact with different liquids or other substances. Some of these exposures break down material properties, such as strength indicated above; others can reduce barrier properties or adversely affect functional properties like moisture barrier breathability or trim reflectivity and appearance. Some loss of performance can be more subtle, such as repeated compression that can cause reinforcement layers to lose insulation or loss of repellent finishes that results in clothing with increased pickup of water weight, reducing some forms of heat insulation.
The degree to which the performance properties are reduced varies with the combination of different exposure conditions and can be affected by other factors, such as the accumulation of soils in clothing materials. For example, research shows that soiled turnout clothing can reflect less heat (i.e., it will provide less insulation to thermal exposures), soiled material composites provide less breathability, and soiled clothing is more likely to pick up water or other liquids, including contaminants.
The degree for which these changes are acceptable and affect service life is subject to considerable debate. In some cases, if samples were removed from the affected gear and subjected to the same NFPA 1971 testing that is applied to new gear, then it is possible in some cases and likely in other cases that NFPA 1971 performance criteria would not be met. Industry experts do not agree on what level of performance degradation would be considered reasonable for field-used gear and what level represents a potential safety hazard. For example, a significant drop in thermal protective performance that reduces insulation from heat should be an area of concern, as would permanent petrochemical contamination that renders gear materials flammable; however, a drop to just below the requirement for tear resistance could still provide a functional level of strength for providing appropriate protection.
How does gear performance change over time?
Some relationships are already known for how gear performance changes from use without extraordinary exposures. For instance, unless contaminated, the types of materials used in turnout clothing generally retain near-new flame-resistance qualities. When gear is worn, layers rub against each other, causing small balls of fabrics and greater “loftiness” of the composite. This type of change increases thermal insulation but decreases breathability as measured by total heat loss. Many strength properties lessen through repeated laundering and use but may still retain sufficient strength level for keeping the gear intact. Water absorption resistance or water pickup will increase over time, but these changes are gradual. Barrier properties may or may not be reduced as films wear down or are damaged, but often can be repaired. These observations assist with framing gear performance expectations in terms of service life but do not create exacting distinctions. Ultimately, departments must apply judgment for whether gear use can be continued, also using the NFPA 1851 procedures for Advanced Inspection.
The reality is that without testing, most fire departments use visual cues and evaluate the cost of repairs versus replacement of garments as their primary means for assessing service life. While several studies have attempted to characterize protective garment performance after field use, the issue remains that no single reliable approach can truly make the “keep or retire” determination. That may change as more science is brought to bear from studies that better detail available inspection methods, as is now being undertaken by NIOSH in a multi-department study where they will be able to track gear history with gear protection changes.
For the time being, service life determinations will depend on the judgment of experienced fire department individuals and subject matter experts with input from the gear manufacturers. These determinations will further account for findings from NFPA 1851 advanced inspections and will most often be related to visible damage of gear following exposures to different hazards on the fireground. If there is nothing from the inspection results, observed damage, or judgment from the department authorities triggers removal of specific gear from field use, then the mandatory 10-year service life specified by NFPA 1851 will limit the maximum gear service life. Without hard and fast rules, most in the fire service are likely to err on the side of safety when there are doubts about continued performance.
Note: The views of the author do not necessarily reflect those of the sponsor.