07 Oct Design and development
Providing October FME readers insight into the design and development process when creating new protective garments is Roger Startin, Joint Managing Director of Bristol Uniforms which for more than 60 years has been at the forefront of firefighter PPE design.
New fibres and fabrics
Technical designers must regularly carry out research into new materials hence work closely with the world’s leading fabric and fibre manufacturers, such as WL Gore, Hainsworth and PBI, to take advantage of the very latest technological advances.
In recent years, huge strides have been made in the development of materials that can at once prevent water ingress from the outside, whilst allowing sweat and moisture to escape from the inside, thereby keeping the body cool. At the same time, firefighter PPE must of course offer robust protection against heat and flame. Fabric manufacturers are continually striving to improve performance, with the aim of creating fabric that is both lightweight and effective. By selecting combinations of these fibres and fabrics, PPE can be developed that offers firefighters the very best protection.
Emerging research
Keeping abreast of topical issues and emerging research that may lead to new requirements for PPE is also an essential task for designers. For example, the industry has long been concerned by high rates of cancer diagnoses amongst firefighters, and exposure to smoke particles has now been highlighted as a possible cause. There is now also significant evidence confirming that the accumulative or acute workplace exposure to Polycyclic Aromatic Hydrocarbons (PAHs), or soot, is directly linked to cancers such as lung, thyroid, bladder and testicular. This kind of information and research feeds directly into new product development, and as a result our design team has been working hard to develop new materials to filter harmful smoke particles.
Standards
Ensuring that products adhere to specific national and international standards for PPE, looking out for any new or amended standards on the horizon, is a constant discipline. The three main international standards setting bodies are the International Standards Organisation (ISO), the National Fire Protection Association (NFPA) and the European Committee for Standardisation (CEN). At the moment we are closely following EN469:2005 – Structural PPE, which may be revised later this year, and EN13911:2017 – Firefighter Fire Hoods, which is also under revision.
New designs and concepts
Research of local and regional demands, challenges, climate and exposure whilst studying the latest developments in the industry and related industries, whilst seeking input from customers and international distributors, and exploring the latest fibres and fabrics on the market is a collaborative process and one which takes many months.
Drawing on the research undertaken, specialist technical designers will then develop new product designs using the very latest Computer Aided Design (CAD) software.
Designing protective clothing is complex and highly-skilled and the garments must address the numerous combinations of health risks, whilst allowing maximum movement and comfort. For example, firefighter clothing must be flame-proof, heat-resistant and water-resistant, but at the same time it is essential that it is breathable to keep the body cool and dry. Equally, it must be light and flexible enough for firefighters to undertake a physically demanding role which is likely to include running, climbing and crawling.
Testing
Once a new product is designed, prototypes are created and put through a raft of rigorous tests to measure safety, protection, comfort and ergonomics, as well as adherence to relevant international standards for firefighter PPE. On the whole, most standard-settings bodies like the NFPA and the CEN want garments to be tested for the same things, but in a slightly different way. Testing is undertaken on composite and single layers, which checks for things like flame and heat resistance, flame spread, heat transfer, breathability, fabric strength, surface wetting, liquid chemical penetration, dimensional change, ergonomics, and visibility.
There is also a non-mandatory mannequin test which checks how garments perform in flash fire conditions. At Bristol Uniforms we often use this simulating test during new product development, so we can identify areas of the body where improvements in protection are required.
Compatibility
Finally, the products are tested for compatibility with all other garments they are likely to be worn with, to ensure top-to-toe protection for a myriad of garment combinations.
Design processes
Structural firefighting ranges must be created in response to the changing role of the firefighter. In a trend replicated across most areas of the world, firefighters are spending much less time fighting fires and more time attending a wide variety of other emergencies such as traffic accidents, medical emergencies, flooding and chemical spills. With this in mind, we started to look at ways of making firefighting PPE more ergonomic and comfortable, and more protective against these new types of hazards.
Various designs will be put forward by the design team, differing in construction, fabrics, shape and look. Each is assessed and the preferred design refined. During this process indicative testing can be undertaken, which is independent testing of selected fabric layers to ensure they work effectively and meet the required standards.
As a result of these processes our final XFlex design features a spiral cut, which means that none of the seams of the garment are straight, but instead follow the body’s curves and contours and allow much more movement and flexibility. The design features shoulder shaping and under arm gussets, which allow full rotational arm movement, and ergonomic three-dimensional articulated elbows and knees. The outer layers are waterproof and protect against heat and flame, and also pathogens, whilst the inner moisture barrier allows sweat to escape and keeps the body cool.
It is certainly a very exciting time for firefighter PPE design. The role of the firefighter is continuing to evolve,
new research is providing greater understanding of potential risks and dangers, and new technologies in protective fibres and fabrics are constantly being developed. Bristol’s design team will continue to lead the way in this field, striving to improve, adapt and innovate to provide the very best protection for firefighters across the globe.