Inspecting and maintaining Ex equipment

Article published in the Regulator | Issue 3: 2017 

Electrical equipment (Ex equipment) on offshore facilities is subject to many factors which affect its deterioration. These factors include bad weather conditions, the age of the facility, mechanical vibration and mechanical damage.

During a production facility inspection, NOPSEMA inspectors discovered that the operator had not inspected Ex equipment (internally) and consequently could not demonstrate that it was fit-for-purpose. Such equipment has the potential to provide an ignition source, such as in the event of an uncontrolled release of flammable material, and could result in fire or an explosion.

AS/NZS 60079 sets out the grades of inspections that should be conducted on Ex equipment in part 17:2009, under section 4.3.3 on types of inspection.

Failure to undertake detailed (internal) inspection is a contravention of clause 9(2)(c) of schedule 3 of the Offshore Petroleum and Greenhouse Gas Storage Act 2006. Specifically, ‘the operator of a facility is taken to be subject, under subclause (1), to each of the following requirements (c ) to take all reasonably practicable steps to ensure that any plant, equipment, materials and substances at the facility are safe and without risk to health.’

NOPSEMA will continue to assess operator compliance with inspection and maintenance requirements. We will also encourage good industry practice for managing Ex equipment integrity. If NOPSEMA inspectors discover that operators are not complying with their requirements to maintain safety-critical equipment, they will undertake appropriate enforcement action. For further information refer to:

  • UK HSE Offshore information sheet no. 1/2011 – Inspection and maintenance of explosion protected (Ex) electrical equipment in hazardous areas (
  • Energy Institute – Guidelines for managing inspection of Ex electrical equipment ignition risk in support of IEC 60079-17 (