CompEx Training Frequently Asked Questions

Gain a better understanding on CompEx Training for sites with explosive atmospheres

CompEx is a nationally recognized qualification supported by the HSE, NICEIC and EEMUA, and is fast becoming a mandatory requirement on many plants. CompEx is the only nationally recognized course and qualification in explosive atmospheres installation and inspection. It provides competence based training and assessment for electrical and instrumentation technicians working in hazardous areas in offshore and onshore industrial environments.

Below are some answers to Frequently Asked Questions about CompEx Training:

How are the units taken?
Intertek provides the following units as these are the most frequently requested by sites with explosive atmospheres.

  • CompEx Full Course Gas & Vapours, units EX01 - EX04: For Technicians (electrical and instrumentation) who may be called on to work in potentially explosive gas atmospheres
  • CompEx Dust Course, units EX05 - EX06: For Technicians (electrical and instrumentation) who may be called on to work in potentially explosive dust atmospheres only
  • CompEx Refresher Course: This course is mandatory within 5 years of gaining your CompEx Qualification. If you do not do the refresher (and pass the test), you will no longer be qualified 'CompEx'. This course can also be taken as an overview of Explosive Atmosphere Installation and Inspection
  • CompEx Exam Only: One or two days of tests and assessments (depending on the units covered) to the CompEx assessment criteria including a theory paper, practical installation and practical inspections. Only recommended for trained, experienced installers

Who is the course aimed at?
Electro-technical personnel who need to develop and demonstrate their competency in the selection, installation, inspection and maintenance of electrical apparatus in potentially explosive atmospheres, through a nationally industry recognized and certificated training and assessment scheme.

What subjects are covered?
Subjects covered include: area classification; temperature classification; gas groups; dust protection; IP ratings; impact protection and other environmental influences; ignition sources; marking and identification; legislation; directives and standards; earthing; bonding; protection methods in detail; Ex'd', Ex'e', Ex'n', Ex'p', Ex'i', Ex'm', Ex'o', Ex'q'; dust protection by enclosure; wiring systems and glanding; installation, maintenance, inspection and testing.

How will I be assessed?
The assessments are both practical and written and can take two days to complete, and follow on immediately from the training. Each candidate is required to demonstrate competence through a series of practical tests and written multi-choice test papers, with successful candidates receiving a CompEx Certificate of Core Competence.

Where will I need to go to be trained or assessed?
Our approved CompEx licensed center is located near the historic city of Chester, UK. For companies outside of the UK who are not able to travel to Chester, we are able to offer CompEx training and assessment through the use of our mobile rigs.

What is DSEAR?
DSEAR stands for the Dangerous Substances and Explosive Atmospheres Regulations and these put duties on employers and the self-employed to protect people from risks to their safety from fires, explosions and similar events in the workplace – including members of the public who may be put at risk by work activity.

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