Since January 1, 2006, every European operator of lines containing explosion-hazard areas has been required by law to draft an explosion protection document under ATEX (“atmosphère explosible”), the collective term for European explosion protection regulations. However, many paint shops lack the knowledge to draft the required forms. To address this problem, BASF Coatings has developed a safety concept based on the current European standards that provides all users of paints assistance in assessing the explosion hazard.

Since January 1, 2006, every European operator of lines containing explosion-hazard areas has been required by law to draft an explosion protection document under ATEX (“atmosphère explosible”), the collective term for European explosion protection regulations. However, many paint shops lack the knowledge to draft the required forms.

“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 from BASF Coatings’ Plant Safety Department in Ludwigshafen, Germany. Waiting until the authorities come knocking or there has been an incident is too late, he said.

To address this problem, BASF Coatings has developed a safety concept based on the current European standards that provides all users of paints assistance in assessing the explosion hazard.

According to Germann, 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.

BASF’s safety concept can be found atwww.basf-coatings.de/en_UK/siko_applicationand includes the necessary calculation programs, as well as background information and other details. An advisory guide for automotive refinishing centers, titled “Explosion protection for automotive refinishing body shops. A guide for drafting explosion protection documents for operators of coating lines,” is available from all Glasurit dealers. Glasurit’s website is atwww.glasurit.com.