ATEX ("atmosphère explosible") is the collective term for European explosion protection regulations. "Operators of paint shops are required to actively explain in the explosion protection document how safe their operations are, but often do not know how. It’s as if you had to make a tax return without having the official form for it," said Wilfried Germann in Ludwigshafen, pointing up the lack of information. Waiting until the authorities came knocking or there had even been an incident was too late, he said.
Germann’s role is to educate. There are three stages in the explosion protection document. Firstly, the possibility of a potentially explosive atmosphere occurring has to be assessed. The following applies for paints and solvents: a potentially explosive atmosphere is present above a solvent concentration of 40 grams of solvent per cubic meter of air. With liquid coatings and solvents this concentration can only be reached if the flash point of the substance is close to the ambient temperature in the presence of atmospheric oxygen.
A potentially explosive atmosphere can even occur when waterborne basecoats are being used, thus when the paint’s overspray is flammable, i.e. during atomization.
The second stage is to assess how frequently the occurrence of a potentially explosive atmosphere must be anticipated. A distinction must be drawn between whether, for example, the release of explosive substances only occurs in the event of leakage, as can happen, for instance, in a warehouse, or whether the substance is released operationally during the coating process. A distinction is drawn between three zones: "Zone 0" (e.g. inside containers), "Zone 1" (e.g. in the vicinity of transfer points) and "Zone 2" (e.g. in the event of leakage or spillages close to ground level, in a paint store or paint mixing rooms or if the ventilation system fails in the spraying station). There is an urgent need for material- and line-specific data to determine the potential hazard.
The third stage consists of identifying and analyzing potential ignition sources. An explosion can only take place if the occurrence of an ignition source coincides with the presence of a potentially explosive atmosphere. A distinction is drawn between ignition sources which occur during normal operation, others that are caused by straightforward faults, and those that come about in the event of rare faults. The degree to which the different ignition sources have to be ruled out depends on the zone in question.
The ignition sources in the coating process can include electrostatic discharges, naked flames, hot surfaces, frictional heat, and chemical reactions.
Wilfried Germann urges all automotive refinishing centers to draw up an explosion protection document. Assistance is available on the internet by visiting www.basf-coatings.de/.... This provides the necessary calculation programs and also gives access to background information and other details. Glasurit has written its advisory guide " Explosion protection for automotive refinishing body shops. A guide for drafting explosion protection documents for operators of coating lines" especially for automotive refinishing centers. It is available from all Glasurit dealers.
Glasurit Automotive Refinish
Under the Glasurit brand, BASF markets a comprehensive range of automotive refinishing paint systems, focusing on eco-efficient waterborne basecoats and high-solids paints. By using these systems all legal solvent-reduction requirements can be complied with anywhere in the world, and with regard to appearance and durability, the products meet the same quality standards as solvent-borne paints. In this area, the company offers a wide variety of services to support its customers. Glasurit Automotive Refinish is approved by most of the leading car manufacturers for aftermarket repair worldwide and chosen by them for its color expertise. Internet: www.glasurit.com