Water utilities (Ex09 – Ex10)

CompEx certification for the water utilities industry

Water utilities (Ex09 – Ex10)

The CompEx Ex09-Ex10 Water utilities qualification has been developed for electrical and instrument operatives working in water supply, wastewater and water treatment sectors where gases and vapours can potentially create a hazardous environment.


This qualification is suitable for workers who operate in the water utilities industry, particularly in intake and storage areas of wastewater treatment plants, wastewater pumping stations, wet wells and gravity fed sewers where there is a risk of explosion.

Entry requirements:

  • Practicing competent electrical operatives
  • Practicing competent instrument operatives
  • Electrical/instrument engineers with previous practical experience
  • Prior CompEx certification supported by employer sponsored letter.


5 days


The 5-day course includes:

  • 3 days of guided learning (theoretical 15-20 hours, practical 4-6 hours)
  • 2 days of assessment

This course has been developed in consultation with industry to ensure the core competence of existing and potential workers who operate in the water utilities industry.

The qualification consists of two separate units which cover the minimum requirements for safe working practices in these areas.

Candidates will learn about legal obligations such as national regulations and the associated directives and standards. They will receive instruction on the associated risks, their categorisation and the difference between hazardous locations and confined spaces. They will also gain an understanding of special situations and conditions, toxic gases, and precautionary measures taken to minimise risks.

Please note: This is not a confined space training course and is NOT a substitute for confined space training.

Key learning objectives

Candidates that successfully complete the Ex09-Ex10 qualification will be able to:

  • Identify the correct national regulations, directives and standards which are applicable to hazardous locations.
  • Identify the correct criteria and descriptors used to classify a hazardous location.
  • Recognise the correct characteristics of common hazardous gases and vapours discussed during the course.
  • Demonstrate an underpinning knowledge of how certified Ex electrical equipment including Ex’d’, ‘e’, ‘n’, ‘p’, ‘m’, ‘o’, ‘q’, ‘s’, Intrinsic Safety (IS) maintains its protection concept and how it is to be selected, installed, inspected and maintained.
  • Identify the correct test value readings for IS and non-IS installations and equipment.

Qualification details

Candidates who are successful in both the theory and practical assessments will receive a CompEx Certificate in Core Competence. 



Assessment is undertaken using both practical assessments and an examination that covers the two separate CompEx units.


Candidates must undertake a multiple-choice examination that consists of 60 questions answered over 1.5 hours.

Practical assessments:

Candidates are required to undertake two practical assessments (one per unit):

  • Ex09 assessment – installation, continuity insulation resistance testing and functional testing – 4 hours
  • Ex10 – documentation, inspection, external supply characteristics testing – 2 hours

Applicable Industries:

  • Water supply
  • Wastewater management
  • Water treatment
  • Associated services

Find a centre

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Retain certification

Achieving CompEx core competency is essential for practitioners who work in potentially explosive environments, but competency must be maintained following certification.


The CompEx resource centre provides all the essential forms, documentation and downloads that you may need for CompEx training and registration

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