New Responsibilities Are Introducing Serious New Hazards
Turnout gear. Bunkers. Whatever the term is that you use to describe your personal protective equipment (PPE), the objective has always been the same: protect. But while improvements in technology and progress in material science have led to the advanced PPE in use by firefighters today, new firefighter responsibilities, emerging threats and a richer understanding of firefighter injuries is forcing a reevaluation of what it means to protect fire personnel.
Where We've Been
The definition of what it means to fight fires - what it means to be a firefighter - has always evolved. The earliest firefighters fought fires from outside buildings - structures were rarely entered. As a result, early firefighter PPE was built for warmth and dryness, not fire protection. Felt caps, wool trousers, wool shirts and a long leather or rubber slicker thrown over the top of it all were the predecessors of today's modernized turnout gear. While the turnout gear worn by early firefighters helped shed water and protected against hazards such as debris, they provided minimal thermal protection.
As technology advances were made, firefighting tactics changed and firefighters were called to enter burning buildings, rather than fight fires from outside. Codes and standards for the protective clothing of firefighters developed by the National Fire Protection Association (NFPA) to minimize the risks associated with firefighting, coupled with advances in fire-resistant materials, helped spur rapid development in protective gear from a number of manufacturers.
In 1973, the NFPA's Technical Committee on Protective Equipment for Fire Fighters began working on a preliminary standard for firefighter protective clothing that would later become NFPA 1971. The standard, which is revised periodically, specified the minimum design, safety, performance and certification requirements for firefighting PPE and required that all gear contain a fire-resistant outer layer, an inner layer to prevent against moisture and a third layer to provide thermal insulation. The requirements put forward by NFPA 1971 formed the basis of today's increasingly complex turnout gear. Developments in technology and materials led to modern turnout gear made from fire resistant fabrics - aramids such as Nomex and Kevlar - and polybenzimidazole (PBI) fibers.
The NFPA standards helped firefighters address their need for thermal protection; however, the definition of what it means to be a firefighter has evolved. The 21st century firefighter is being asked to do more than ever before - in fact, today a firefighter is more aptly described as a first responder. As firefighters are asked to do more, it is only natural that the gear that they wear address new responsibilities, new hazards and a new understanding of the causes of life-threatening injuries.
New Responsibilities
Estimates vary, but there is general agreement that more than 70% of the incidents that firefighters respond to do not involve "structural" firefighting. Firefighters are called on to respond to virtually any kind of natural disaster including - perhaps paradoxically - floods. Furthermore, firefighters are increasingly expected to provide a full range of emergency medical services, thereby introducing them to dangers such as blood-borne pathogens that emergency medical technicians are automatically equipped to face.
The acquisition of new responsibilities has not always been coupled with the acquisition of new PPE. Traditional turnout gear is heavy and designed with one purpose - thermal protection. Newer multi-purpose garments add liquid-chemical and liquid-pathogen resistance, which provides greater flexibility, but are not necessarily the best garments for any one task. In any case, the heavy gear can actually be counterproductive in certain situations and causes tremendous heat stress. Protecting firefighters from the challenges posed by new responsibilities is no simple task. Nevertheless, the industry as a whole needs to find a solution, because the new responsibilities are introducing serious new hazards.
New Hazards
Protecting oneself against blood-borne pathogens is one thing, but today's firefighters are also expected to be among the first wave of responders reacting to a chemical, biological, radiological or nuclear (CBRN) incident. While the chances of such an incident remain low, the fact remains that traditional thermal protection is wholly inadequate to protect firefighters in such a scenario. The new NFPA 1971 2007 edition does provide an option for CBRN protection, but will cost more, further encapsulate the user and potentially contribute to even higher heat stress. Additionally, there is currently no data on protective performance covering the life of the garment.
Unfortunately, traditional thermal protection is often the only PPE firefighters are provided. This is because the acquisition of different types of PPE to meet different challenges can be a budget buster. New standards call for building chem/bio protection into standard turnout gear, but this remains an option, not a requirement, and much work needs to be done. Furthermore, the development and availability of multi-purpose PPE sidesteps other problems.
New Understanding
More than 100 U.S. firefighters are lost every year - half due to stress and overexertion, which can lead to heart-attacks and other life-threatening ailments. These threats aren't caused by fires, floods or CBRN incidents. Firefighting is a strenuous occupation and the use of bulky and restrictive protective apparel can contribute to stress. Turnout gear is designed for 20 minutes of use. The more firefighters work while wearing turnout gear, the greater the stress they put on their bodies.
Additionally, firefighters and manufacturers are learning more each day about the problem of moisture or air trapped between the skin and the gear. Most burn injuries occur with minimal damage to the PPE. Firefighter PPE is tested to 500 degrees Fahrenheit for five minutes to demonstrate stability. However, what's good for the PPE isn't good for the firefighter. At excessive heat, the layers of equipment directly against the skin (face cloth, hoods and stationwear) heat the skin faster than it can naturally cool itself. This leads to most of the burns today's firefighters experience. The problem is further exacerbated by the fact that turnout gear is traditionally tested in high-intensity, low-duration flash fires. The problems of heat stress and the burns caused by trapped moisture occur in low-energy, long-duration situations - situations that can be challenging to design tests for.
A Way Forward
These new responsibilities, hazards and understandings combine to create a difficult and challenging future for the 21st century firefighter. Multi-purpose gear may not adequately address the challenges of heat stress or protect against burns caused by low-energy, long-duration exposure. New outer shell constructions continue to improve abrasion, cut resistance and flame durability. New static nonwoven thermal liners offer improved balances of garment breathability and thermal protection; however, the trends have been to reduce thermal protection to almost unacceptable levels. New active materials reacting to the thermal environment offer potential for innovative composite and garment designs. Wardrobes of PPE with a multitude of protective options tailored for a multitude of threats is cost-prohibitive. So where do we go from here?
There are no easy answers, but perhaps the place to start is to realize that turnout gear really is the last line of defense. Fire departments and municipalities need to start with a good foundation of work practices to ensure that firefighters are properly trained with the appropriate standard operating procedures (SOPs) to survive the threats they will be exposed to. We need to make sure that all responders have the right foundation to ensure that when events occur responders know what the right steps to take are, and know to take them.
Another path is to remember that the NFPA 1971 standard will open for public proposals soon; users are encouraged to propose changes to the document to meet their needs. The NFPA standards are developed through a consensus standards development process and needs user input to identify the ever-changing needs of the firefighter community.
USFA & NIST Issue Report on Thermal Imaging Technology
The U.S. Fire Administration (USFA) and the National Institute of Standards and Technology (NIST) have completed a report, Technical Note 1499, Performance Metrics for Fire Fighting Thermal Imaging Cameras - Small- and Full-Scale Experiments. The report provides information on the research conducted as part of a partnership on thermal imaging camera (TIC) imaging performance metrics and test methods. The objective of the report is to provide science-based information to national standards developing organizations, including the National Fire Protection Association (NFPA) in support of NFPA 1801, Standard on Thermal Imagers for the Fire Service.
The study was conducted with support of the Department of Homeland Security's (DHS) Science and Technology Directorate. The report describes performance metrics on TIC image contrast, effective temperature range, resolution and image and thermal sensitivity.
"Each year fires in structures trap firefighters resulting in their injury and sometimes death," said U.S. Fire Administrator Greg Cade. "This research partnership has developed critical information to support the development of a national standard on thermal imaging technology that previously did not exist which will enhance the safety of our nation's firefighters."
NIST and USFA conducted research on the performance of thermal imaging systems to enhance firefighter safety in operational situations. Current thermal imaging technology was assessed by investigating a variety of commercially available thermal imaging cameras in the laboratory as well as in full-scale burns. The research also explored new technology that might enhance performance of future thermal imaging devices and worked to incorporate new technology into enhanced infrared cameras. Issues such as differential resolution, thermal exposure, performance during suppression, and ease of use were also examined. This project complemented existing NIST funded research on the development of a standard on thermal imaging technology.
Another technical report documenting the needs of the fire service community, Thermal Imaging Research Needs for First Responders: Workshop Proceedings, was previously published as part of this study. These reports are available for download, free of charge, from the USFA and NIST websites. Further information may be found on the USFA website at http://www.usfa.dhs.gov/fireservice/research/safety/nist3.shtm.
RICH YOUNG, Ph.D., is a senior research chemist at E.I. du Pont de Nemours & Co. Inc./DuPont Personal Protection. Of his 23 years with DuPont, he has spent the past 10 working on fabrics and systems for protective apparel. Dr. Young is a senior member of the market support and product development team for thermal protective apparel. He has several patents on fabric and component technologies and has worked with various technical committees on developing new thermal test methods. Dr. Young earned his bachelor's degree in chemistry at California State University, Sacramento, and received his doctorate in organic chemistry from Michigan State University. He is a member of the National Fire Protective Association (NFPA) Technical Committees for Stationwear and Technical Rescue Gear and works with the Technical Committees on Structural and Proximity Gear.