KERMEL/S.Dezetter - picture caption: El personal expuesto al calor o las llamas en su tra- bajo debe ir equipado con una ropa de protección adecuada. calidad desde el mismo principio de la cadena de valores, hasta el momen- to final, cuando el usuario recibe el producto terminado. La cadena de valores para el vestuario que protege contra calor y llamas, comienza por la fibra, que luego se transforma en hilos que formarán un teji- do, que a su vez, será el material con el que se confeccionarán las prendas. La fibra La fibra conforma el elemento básico de los tejidos y demás estructuras texti- les. El tipo de fibra que debe usarse para el vestuario que protegerá contra altas temperaturas y llamas, pertenece a la familia química de las meta ara- midas, una fibra que se caracteriza por su robustez, y en particular por su excelente resistencia al calor y el fuego, durante toda su vida útil. Las fibras de meta aramidas más conocidas que se utilizan en el vestuario de protec- ción contra altas temperaturas y fuego son: Kermel, Nomex y Conex. El hilo No se pueden utilizar las fibras en crudo para confeccionar prendas. De modo que hay que convertirlas en hilo, mediante el proceso del hilado que va retorciendo las fibras hasta formar un hilo continuo. Este hilo se utilizará When is Protective Clothing not Protective Clothing ? *Alec Feldman In the field of purchasing, there is a well-known warning “Caveat Emptor” which translated from the Latin means “let the buyer beware”. In general terms, this aims to caution the Buyer that no matter what the Seller says about the product /service being purchased, the Buyer has a responsibility to satisfy themselves that what they are buying is what they believe they are buying. The principle Caveat Emptor is particularly relevant when considering buying products/services that are to protect persons from potentially mortally dangerous exposures. In this field of activity, many sellers make claims about the products/ services being offered that at best are not quite accurate and at worst are false and can result in injury or death due to inadequate or unprotected exposure of the wea- rer/user of the product/service. Clothing to protect persons from the effects of heat and flame is a case in point. The purpose of using such protective clothing is to allow persons to work in environments where without the protection afforded by the clothing, they normally could not work without the risk of injury or death. If the clot- hing that is purchased is below the specification stated and required, failure could seriously injure or kill the wearer. A person who wants to buy an item for personal or household use generally knows in detail what features and performance that they require before they buy it. Usually they will specify their requi- rements to the salesperson and will have enough knowledge of the product they wish to buy to be able to evaluate whether the claims made by the seller are valid or not. On the other hand, when items are purchased that could save one’s life, it is the writer’s experience that the potential pur- chaser has little knowledge of the features required and usually what the seller claims about the pro- duct is accepted without question. Perhaps this is because in this area of activity, the purchaser does not know the questions to ask ??? Purchasers should be aware that there are International mini- mum specifications for the purchase of all items of Personal Protective Equipment (PPE). “Purchasers should know what the clothing is expected to do” Where there is a risk that personnel may be exposed to heat and/or flame in their work place, they should be issued with suitable protective clothing. So that they make the correct choice of such clothing, purchasers should know what the clothing is expected to do. The role of such clothing is initially to act as a flame shield when exposed to sudden flame i.e. a barrier between the wearer and the flames, and to provide protection against heat transfer from the flame/heat source. It should also provide protec- tion for the wearer as they escape from the exposure. This type of protective clothing should provide the required level of thermal protection consistent with the potential risk to which the wearer might be expo- sed and escaping from and for its lifetime, should not burn, melt or disintegrate on exposure to flame. It should also provide mechanical protection i.e. resistance against tearing, abrasion, seam splitting and where relevant and subject to its intended use, it may also need to provide conspicuity, protection against the weather i.e. rain, snow, cold, etc. and protection against chemicals. In such an area of activity where failure of protection is essential and is not an option, it is critical that the product is purchased from sources where there are continuous checks and testing of the pro- duct to provide the manufacturer, purchaser and User a level of certainty that the protective clothing being purchased is what is known as “fit for purpose” i.e. it will do what is expected of it within the environment in which it is expected to perform. The final production of items of protective clothing is a result of passing through a “value chain” i.e. a chain of activities whereby products pass through a line of stages of manufacture and at each acti- vity the original raw material is subjected to manufacturing processes that assist on its way to beco- ming the finished product. Reputable Organisations who produce quality products that perform as it is claimed they perform, rigidly impose standards of performance and of quality from the beginning of the value chain until its end, when the User takes delivery of the final product. The value chain for clothing to protect against heat and flame commences as a fibre, which is manufac- tured into yarns, the yarn is manufactured into fabric and the fabric is manufactured into the clothing. 53 EPI: MATERIALES, MAQUINARIA Y TÉCNICAS PARA SU FABRICACIÓN/ PPE: MATERIALS, MACHINERY AND TECHNIQUES FOR THEIR PRODUCTION