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It should come as no surprise that structural firefighting footwear is probably one of the dirtiest components of the ensemble following use on the fireground. After all, if there is one clothing item that is in near-constant contact with the fire scene, it’s the boots firefighters wear.
Let’s consider how firefighter footwear is evolving and what to expect in the future, taking a close look at some possible upcoming changes for the standard that defines footwear design and performance.
Advances in firefighter footwear
Several decades ago, firefighters wore long coats and hip boots. At that time, the boots were more or less “waders” that extended high on the leg to provide lower leg protection and were exclusively constructed of rubber materials often with interior textile linings.
Even after hip boots became passé, a large volume of the footwear worn by firefighters continued to be made of rubber. Rubber was considered to be relatively waterproof for keeping firefighters’ legs and feet dry, plus more protective and durable. However, these boots tended to be relatively heavy and sometimes did not provide adequate ankle support, which could be a problem since firefighters regularly traverse uneven surfaces, especially during aggressive interior fire operations.
Leather boots have been around for a long time for different occupations and firefighting is no exception. Rugged work boots with steel or composite toes are the mainstay of many worker populations, and these boots have been adapted for firefighter purposes over the past several decades. The key is ensuring that boots are flame resistant, which is generally the case for most leather, and providing sufficient insulation to high heat in combination with interior layers being “waterproof” and having the requisite physical protection features.
Decades ago, rubber was the more common style of firefighter footwear, but today, many firefighters wear leather boots, generally because they are lighter in weight, offer greater ankle support, and provide a sufficient level of physical and thermal protection on the fireground. Many of these boots have further evolved into an athletic fit for greater ergonomic performance in terms of their comfort and impact on firefighter agility.
Different leather boot designs have emerged, from regular step in or pull-up boots to those with sophisticated zipper and lace arrangements for fast donning and doffing. Rubber boots have also been redesigned to be lighter and more flexible as well as provide improved fit. Multiple improvements have been offered by several manufacturers to address the adequate levels of sizing and function.
The impact of standards
Part of this transition has been brought about by the existence of NFPA standards relative to firefighter footwear. The very first standard – NFPA 1974 – was promulgated in 1987.
At that time, footwear requirements were relatively simple – boots had to be 8 inches high, have a defined heel, and be available in both a range of men’s and women’s full and half sizes in at least two widths. Performance criteria focused on boot heat and flame resistance, and introduced two tests for both conductive and radiant heat resistance as a means for providing minimum thermal insulation.
Physically, boots were required to meet an American National Standards Institute (ANSI) requirement for toe impact and compression resistance as well as having upper materials that demonstrated adequate puncture and cut resistance and sole materials that resist abrasion. Boots were required to have a ladder shank (to stiffen the outer sole) and any metal parts had to be corrosion resistant. The new standard further included a test for boot leakage after 100,000 flexes of the boot to simulate wear and required boots to be electrically resistant.
Fast-forward to today, and there have been six different editions of NFPA standards that have addressed structural firefighting footwear. In 1997, the third edition requirements became a consolidated standard for the full ensemble in NFPA 1971: Standard on Proximity Ensembles for Structural Fire Fighting and Proximity Fire Fighting, which included boots as well as garments, helmets, gloves and hoods.
The most recent edition of this standard in 2018 was the result of several changes and new requirements that addressed footwear design and performance. For example, several years ago, the minimum boot height was raised to 12 inches, then back to 10 inches with additional criteria set for the height of waterproof layers and physical performance of the boots. While some performance requirements have remained the same, new areas have been added for liquid chemical and fireground liquid penetration resistance, outer sole traction, and the attachment strength of eyelets. Newer tests have been adopted for flame resistance, liquid integrity and sole abrasion resistance.
Nevertheless, if you examine the types of properties that boots are subject to for being qualified as structural boots, the list of performance attributes has changed only mildly over the years of boot design and performance standardization. More attention has been placed on other parts of the ensemble, namely garments, helmets and, to a lesser extent, gloves.
Boots and fireground contamination
Though contamination concerns have primarily focused on garments, there has been an ongoing recognition that footwear should also be considered because boots are subject to contact with fireground soot and other soils and are easily contaminated.
Back in the early 2000s, one vendor study that examined boot contamination with hazardous materials found that rubber boots were more likely to retain certain contaminants compared to leather boots. Further, we know that other differences in footwear construction and materials can contribute to firefighter secondary exposure to contamination and ease of cleaning following exposure in a fire. Just how persistent some of this contamination is remains unknown, although work being undertaken by the NFPA’s Fire Protection Research Foundation has shown varying degrees of footwear contamination on both the exterior and interior of different types of boots. In many cases, contamination levels on the inside have been the same or higher than on the outside. Related research is underway to examine the efficacy of certain cleaning methods, such as manual washing and ultrasonic cleaning, in removing any persistent contamination.
Most firefighters are likely to have a single pair of structural boots that are separate from any station or regular work boots. Nevertheless, boots tend to be infrequently cleaned because the process for cleaning them is timely and can take the boots out of service while they are being dried. This can disincentive addressing boot contamination. It further means that boots can be a continuing source of contamination exposure while being worn as well as being brought back to the station in the apparatus and vehicles.
Contemplation of new requirements
NFPA 1971 is in the process of revising its standards for structural firefighting clothing, including boots.
For the next edition of the standard that will issue sometime in late 2023, several changes that are responsive to contemporary needs are under consideration:
- Reconsideration of the minimum height of footwear to allow graduated heights for individual firefighters of different stature;
- Improvements to how footwear liquid integrity is measured;
- Assessment of liquid absorption and drying time;
- Evaluation of footwear flexibility that may be related to agility; and
- Introduction of an optional footwear breathability test.
Each of these proposed areas is an attempt to address aspects related to either footwear comfort or performance that may be pertinent to its contamination and cleaning. Short of an actual contamination and cleaning test, which is still a separate area under consideration, the hope is that the new metrics will result in encouraging further improvements to address ergonomic and contamination resistance features. Some manufacturers are already proceeding in this direction, and the potential adoption of new requirements may drive this process.
Understanding fire service needs
There is a large range of footwear options for firefighters in today’s marketplace. Consequently, there are many good choices available to individual firefighters, though departments make the general choices for what firefighters must wear as part of their structural firefighting duties. Consequently, understanding whether firefighters’ needs are being addressed is an important step in the consideration of any new direction in footwear product development and qualification. As such, we developed a short survey on the topic to better understand the issue. We hope to get feedback back from you on this subject to help inform the NFPA 1971 committee about potential new directions in structural firefighting footwear certification. We hope you’ll participate in the firefighter footwear survey.
Note: The views of the author do not necessarily reflect those of the sponsor.