Measures Are Obligation

According to 2014/34/EU Annex 1, the manufacturer must divide any equipment that can present ignition hazards (ignition sources) and lead to explosion into device groups and categories. For this equipment, an Ex type test and certification from one of the testing offices named must be conducted. If the device fulfills the requirements for the type test, the basis for the CE mark follows with the EC declaration of conformity. The equipment must come with operating instructions in which its proper use is defined.

The primary concern is to prevent explosive atmosphere from forming, preferably by selecting non-flammable alternatives or materials that have a high flash point. If this is not feasible for whatever reason, the focus turns to other measures. For one, inertization. Here it is possible to take advantage of the property that an atmosphere only becomes explosive at an exact mixing ratio of a flammable material with oxygen.

This measure aims at preventing an ignition of dangerous explosive atmosphere if the arising of these cannot be avoided. For this, areas must be divided into danger zones in the application location according to the frequency and duration of the occurrence of explosive atmospheres. These define whether or not sources of ignition are permitted in particular danger zones. Click here for an overview of the ignition sources.

It is not always possible to safely prevent the occurrence of a dangerous atmosphere and to exclude an ignition of suitable resources. In this case, additional explosion protection measures must be taken in order to reduce the effects of an explosion to a harmless level. The measures for constructive explosion protection include, in addition to pressure-proof and impact-proof housings, pressure reduction and pressure equalization equipment. Explosion suppression through extinguishing devices also counts toward this.

Requirements for Manufacturers and Operators