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RESEARCH & DEVELOPMENT DRIVES PPE INNOVATION
PPE INNOVATION
water protection, moisture vapour permeability and wearability as well as the need to constantly look at ways of improving the compatibility of various elements of PPE when worn in combination.
The role of fibre and fabric manufacturers A robust and efficient supply chain committed to meeting the needs of the specialist PPE market is essential for the smooth working and international competitiveness of the UK’s firefighter PPE manufacturing sector which has worked closely with both the fibre producers and fabric weavers for many years. This close cooperation has led to an unrivalled understanding and appreciation of each other’s needs within a supply chain which is also recognised as one of the most highly developed anywhere in the world today. The chain begins with the world’s leading fibre producers which are, in the case of firefighter PPE, Dupont, PBI Performance Products Incorporated and Kermel. These companies in turn supply directly, or indirectly through yarn spinners, the leading fabric weavers including A W Hainsworth & Sons Ltd and Heathcoat Fabrics Ltd in the UK. The origins of this supply chain collaboration lie in the pioneering work undertaken by Bristol Uniforms as early as the 1960s and further developed in the mid 1970s when discussions between Bristol and Dupont led to the introduction of the first Nomex outershell product in 1980. Named Nomex III, it was introduced by Bristol Uniforms to the fire market and was made from a 265gsm blend of 95% Nomex fibre and 5% Kevlar. This was followed by Nomex Delta T, a 195gsm blend of 75% Nomex fibre, 23% Kevlar and 2% antistatic, in 1990. During the 1990s Delta T steadily superceded Nomex 3 and became one of the leading outershell fabrics throughout Europe. In 2000 Hainsworths introduced their current class leading fabric, Nomex with Ti-Technology. This is an entirely new construction with a weight of 220gsm and uses a dual layer advanced woven fabric system with a 95% Nomex and 5% Kevlar outerlayer interlocked with a 100% Kevlar grid on the inner side. Differential shrinkage of the two layers is accommodated by the bonding process of the layers using a Nomex fibre yarn providing improved wearer protection against heat from flash fires. Bristol was the first firefighter PPE manufacturer to introduce these fabrics into their garments. In the mid 1990s Heathcoats entered the market 52
to supply outershell fabrics for firefighter garments. By using PBI fibres from PBI Performance Products Incorporated which accept dyes, the company has been active in the development of colour variations to PBI Gold, the natural colour. In recent years both navy and red have been made available for new PPE introduced by Bristol. The characteristics of today’s major fibres used in fabric combinations have been available for some years. This has allowed the fabric weavers the scope to apply their technological and design skills to the development of new constructions which have become available to the manufacturer for firefighter PPE applications. Over time, the improved understanding of fibre performance has made possible the development of different weave ratios to give improved performance. WL Gore & Associates are a leading membrane manufacturer supplying the intermediate layer which provides the thermal and moisture barrier within the garment construction. Products such as GORE-TEX® Laminate with AIRLOCK® Spacer Technology, GORE-TEX® Fireblocker Laminate and Crosstech® Laminates form a range of membranes developed specially for fire garment use and provide high performance protection. Gore use a blended aramid substrate to provide strength in their nonwoven constructions. Finally each garment has an inner lining. A number of companies, mainly French and German, manufacture firefighter garment linings. Using principally aramid fibres, the linings are normally supplied through specialist quilters before arriving at the garment manufacturer.
The garment manufacturer’s role – bringing it all together The contribution of the garment manufacturer in the performance and comfort of the final product is a combination of a number of things including; ● Selection of the best individual layers which in combination deliver the right technical and comfort characteristics ● The knowledge and skills required to design the combinations so that they can be brought together without compromising the performance of any individual component ● Accuracy of measurement in fabric cutting combined with skilled machining to produce durable and well-finished garments ● Attention to detail in garment sizing to ensure good fit and wearer comfort for both male and female users ● Careful selection of trim and finishes to achieve the specified in-service performance of the user ● Manufacturing methods which result in garments which are not only durable but have the required longevity to undergo regular maintenance under a managed care programme which involves frequent washing and drying as well as periodic decontamination, depending on service exposure experience. All firefighter PPE is required to meet one or more national, European or international standards. The most widely specified throughout Europe and many other parts of the world is EN 469:2005 and garment design must ensure that in combination the layers of fabric perform under test to meet or exceed the required levels of protection against flame, heat, water penetration and breathability. Firefighter garments include not only fire coats and trousers but also gloves, boots, flash-hoods, helmets and underwear. These all need to work effectively in combination and the fire coat and trouser manufacturer has a responsibility to ensure compatibility between these and the other PPE to afford flexibility of choice for users between a ASIA PACIFIC FIRE