3420 EI Research report: Investigation into the ignition risks due to the ageing effects of Ex electrical equipment

Overview:

The presence of ageing explosion-protected (Ex) electrical equipment in hazardous areas related to potentially explosive atmospheres, onshore and offshore, causes serious concern for those responsible for its operation and maintenance. This publication illustrates and highlights four main modes of degradation that lead to eventual failure of Ex electrical equipment to meet certification requirements and possible catastrophic failure:

• corrosion;
• water ingress and inadequate gaskets/seals protection;
• degradation of plastics (e.g. glass reinforced plastic (GRP)) enclosures and components, due to ultraviolet (UV) or other environmental factors, and
• absence of adequate labelling/ID of equipment to confirm its type of Ex protection
  related to its location.

This publication does not give recommendations as to the frequency of inspections for ageing Ex equipment, but acknowledges that the frequency and degree of inspection will depend on a number of factors, including the age of the equipment and severity of environmental conditions.

The investigation for this publication was carried out by Intertek Testing and Certification Ltd. on behalf of the EI's Electrical Committee to report on ageing Ex electrical equipment.