Conclusiones En el mundo hay requisitos de salud y seguridad, establecidos para proteger a los empleados de las empresas. Por su parte, los empleadores también tienen la responsabilidad de asegurar que sus empleados estén protegidos, una obli- gación que se pasa por alto si el departamento de compras no conoce los peli- gros que subyacen a un accidente, o los subestiman en aras de ahorrar y redu- cir costos. Aquel que toma la decisión de la compra de vestuario de protección es el que establece los parámetros de la organización o compañía para proteger a quienes deben vestir tales prendas. Por eso, la toma de decisiones debe efectuarse con conocimiento de los riesgos contra los que se supone que pro- tegerá el equipo, y antes de elegir el vestuario de protección, tendrá que rea- lizarse una evaluación de riesgos del lugar de trabajo con el fin de determi- nar qué tipo de vestuario de protección será el más adecuado para los empleados que deban llevarlo. Los encargados de las adquisiciones saben que en toda decisión de com- pras hay elementos y factores esenciales. Será decisión del comprador si KERMEL/SDIS68 - picture caption: La ropa hecha de fibras de aramida ofrece la máxi- ma protección frente al calor, las llamas y el arco eléctrico. - Fibre: Fibre forms the basic element of fabrics and other textile structures. The type of fibre that should be used in clothing to protect against heat and flame is in a chemical family called meta-ara- mid, a fibre that is characterised by its strength and in particular, its excellent resistance to heat and flame throughout its lifetime. Well known meta-aramid fibres used in clothing to protect against heat and flame are Kermel, Nomex and Conex. - Yarn: Fibres in their raw form cannot be used to make clothing. For this purpose, they must be con- verted into yarns and the process used for yarn formation is spinning, the twisting together of fibres to form yarn. Yarns are used to construct the fabric and are also used to manufacture threads to sew the fabric together as a garment. A meta-aramid yarn results from spinning meta-aramid fibre. - Fabric: The conversion of yarns into fabric is a major change in physical form. In manufacturing fabrics for clothing to protect against heat and flame using inherently flame resistant fibres, other factors are taken into account subject to the ultimate end use of the garment. These factors include structure, weight, comfort, strength, resilience, colour etc. Other factors may also need to be consi- dered subject to the proposed ultimate end use e.g. water/chemical resistance, visibility, protection against electrostatic discharge etc. Fabrics manufactured from meta-aramid yarns will be mixed with other special high quality fibres to provide these required features in the fabric that in the next stage of the value chain will be used to manufacture the garment. - Garment : The garment manufacturer designs into the garment the features that it is expected the ultimate purchaser will require – type and location of pockets, closure systems etc. With clothing to protect against heat and flame, the designer must ensure that the design of garment will provide protection to the upper and lower torso including the arms to the wrists and the legs to the feet in the event of unexpected flame engulfment of the wearer. The thread that is used to sew the critical parts of the garment should be thread made from meta-aramid or other inherently flame resisting yarn. If for example, the thread used at the main seams of the garment is not of such quality, when exposed to flame it will melt or burn and the garment will fall apart, thus exposing the wearer to possible direct contact with the flames/heat source. At all stages of the value chain, reputable manufacturers will continually carry out sampling and tes- ting to verify that protection and quality of the product are maintained. At the stage of garment manufacture, the garments will be tested and certified by an independent testing laboratory to eit- her CEN (European), NFPA (American) or ISO (International) standards for the type of protective clothing for which the end use is intended. Such tests are destructive tests of fabric and/or garment and so it is very important that the garment manufacturer can adequately demonstrate that gar- ments of the same design, content and quality of the garments/ fabrics that successfully passed the relevant CEN/NFPA/ISO tests are being made by the manufacturer on a consistent basis. Sale to User In a quality value chain, there will be no passing on from one stage to the next until the manufac- turer that is to receive the product is quite satisfied that what they are to receive and to take to the next stage of the chain is of a level of quality that is acceptable by all concerned. Each organisation engaged in each stage of the value chain should be able to produce third party verification of qua- lity in production and other activity. This means that when the final stage of the value chain is rea- ched and the purchasing decision can be taken, the potential purchaser can establish the quality of product from the beginning of the manufacturing process along the value chain to the finished pro- duct i.e. the clothing to be purchased. After purchase, the User should have in effect procedures for the use, inspection, care and maintenan- ce of the protective clothing. Unless the protective clothing purchased is of Internationally recognised quality and certified to the minimum performance levels required by CEN/NFPA/ISO when it begins its life of use, all efforts to control the protective ability of the clothing in use will come to nothing. “The Empero’s New Clothes’ The famous Danish writer Hans Christian Andersen wrote a well-known tale entitled “The Emperor’s New Clothes”. This tale has some very close similarities with the purchase of clothing to protect against heat and flame. The tale tells of two weavers who make false claims about the product they 55 EPI: MATERIALES, MAQUINARIA Y TÉCNICAS PARA SU FABRICACIÓN/ PPE: MATERIALS, MACHINERY AND TECHNIQUES FOR THEIR PRODUCTION