How to identify whether you need a CompEx electrician
Any qualified electrician can take care of basic electrical installations, but not every electrician is qualified to work in hazardous areas (which requires a CompEx electrician). Manufacturing facilities often require more than the basics, so it’s important you get the right electrical contractors for the job.
CompEx (meaning Competency working in Explosive atmospheres) refers to a recognised worldwide training and assessment scheme to ensure those working in hazardous or explosive environments are fully trained and competent.
In other words, CompEx-accredited electricians know how to work safely in the potentially hazardous areas of your facility.
What is classed as a hazardous area or explosive atmosphere?
ATEX derives from the French term ‘Atmosphères Explosives’ (explosive atmospheres) and is the common term for two EU workplace directives.
In the UK, the requirements of the ATEX workplace directives are covered through the Dangerous Substances and Explosive Atmospheres Regulations (DSEAR).
Dangerous substances include any substances that put people’s safety at risk from explosion, fire, or corrosion of metal, including petrol, LPG, varnishes, paint and certain types of combustible and explosive dust.
Where hazardous areas are present, the employer must:
• Identify dangerous substances and assess the risk
• Put measures in place to remove or control those risks
• Put controls in place to minimise the effects of incidents involving dangerous substances
• Outline procedures to deal with accidents, incidents and emergencies involving dangerous substances
• Ensure employees are properly informed about and trained to control or deal with the risks
• Identify and classify areas where explosive atmospheres may occur and avoid ignition sources in those areas
DSEAR defines hazardous areas as "any place in which an explosive atmosphere may occur in quantities such as to require special precautions to protect the safety of workers". A set of zones was introduced to help with classification and hazard management.
Zone 0 is where an explosive gas atmosphere is present continuously or for a prolonged period.
Zone 1 is where an explosive gas atmosphere is present as a normal operation.
Zone 2 is where an explosive gas atmosphere is unlikely as part of normal operation or will occur for a short period.
Unzoned areas are classified as non-hazardous or safe areas.

When should you choose a certified CompEx electrician?
You can choose to partner with a CompEx-certified electrical contractor whether you are required to or not, but there are certain situations when it can be particularly beneficial.
When required under DSEAR or industry regulations
If your workplace has hazardous areas or potentially explosive atmospheres, then you should absolutely choose a contractor with CompEx accreditation. Working with a CompEx-accredited partner ensures that you are doing everything possible to protect your staff and mitigate risk.
If you aren’t sure whether you have any hazardous areas, a CompEx-accredited partner can help you with the classification of zones so that you are compliant under DSEAR.
You should also check your local and industry-specific regulations regarding electrical work. Some industries mandate the use of CompEx electricians to comply with safety standards.
When recommended or required by insurers
Certain insurance policies might require or recommend the use of CompEx-certified personnel to mitigate risk. In some cases, you may even benefit from lower insurance costs if you work with a CompEx-accredited partner.
Working with CompEx partners demonstrates your compliance with safety protocols, reducing liability and potential financial loss.
When the nature of the work is complex or high-risk
Evaluate the type of electrical installation or maintenance required. High-risk environments or complex installations might necessitate the need for a CompEx-certified electrician. They are trained to handle specific challenges in explosive atmospheres. Their expertise can prevent accidents and ensure the integrity of electrical systems.
When CompEx electrician stated in project specifications or under contractual obligations
If you are managing a project on behalf of another company or organisation, check the project specifications, requirements and related contracts for any mention of CompEx certification. Some projects may explicitly state the need for CompEx-qualified electricians. Fulfilling such requirements is crucial for maintaining business relationships and meeting contractual obligations.
When quality is paramount
CompEx-certified electricians undergo rigorous training and continuous education to ensure they remain up to date with the latest safety standards and technological advancements. Working with a CompEx-certified electrician reduces the likelihood of errors, increases the reliability of electrical installations, and ensures a high standard of workmanship.

Protecting your business with AES CompEx electricians
AES offers all the services you would expect from an electrical contractor, coupled with specialist services specifically for manufacturing businesses.
Our industry accreditations include NICEIC, CHAS, SafeContractor, IPAF, PASMA and CompEx.
Our accredited team are competent in selecting, installing, inspecting, and maintaining electrical apparatus in potentially explosive atmospheres, in line with all UK and EU legislation.
Working with us is a best-practice approach to preventing serious incidents. We provide a professional service with a full audit trail to ensure that the correct precautions are followed according to health and safety guidelines and regulations.
We can also help you fully assess your areas and ensure that the zones are classified correctly in line with DSEAR.
Plus, we can scale our services to meet the needs of your business, from ongoing planned maintenance and fault repair to machinery installation and factory relocation.
Contact our friendly team to find out more or book a free energy audit.
Beyond Lux Levels: What a Good Industrial Lighting Survey Should Measure
During a lighting survey, the most revealing moment is sometimes not the meter reading. It is when an operator leans into the task, shifts a component towards the light or reaches for a torch beneath a hood. The wider production area may appear bright, yet the exact place where a seal is checked, a surface […]
Read more
From Risk Assessment to Zone Drawing: What Good DSEAR Documentation Looks Like
A zone drawing can look reassuringly definite. Coloured boundaries, zone numbers and equipment references give the impression that a complicated risk has been reduced to a clear plan. Yet every line on that drawing depends on decisions made elsewhere: which substances are present, where they could be released, how ventilation behaves, what happens during cleaning […]
Read more
Industrial Submetering: Turning One Energy Bill Into Actionable Information
The total at the bottom of an electricity bill can tell a manufacturer how much energy the site has bought. It cannot explain which production line used it, whether demand rose because output increased, or why consumption remained high long after the last shift ended. By the time those questions reach the monthly review meeting, […]
Read more
You Cannot Secure What You Cannot See: Building an OT Asset Inventory
A production line rarely arrives as one neat, self-contained system and stays that way. It acquires a replacement drive here, a new HMI there, a remote support connection added during an urgent breakdown, and perhaps a reporting link into the wider business network. Each change may be sensible on its own, yet over several years […]
Read more
BS 7671 Amendment 4: What Industrial Sites Need to Review Before October 2026
A change to the Wiring Regulations will not stop a production line on the day it is published. Its effects are usually felt more quietly: in a design decision, a procurement specification, a shutdown plan or a certificate that has to stand up to scrutiny months later. For industrial businesses, that makes the transition to […]
Read more
Power and Distribution: Ensuring Load Capacity Matches Modern Demands
Manufacturing sites have changed significantly over the last decade. Many factories are running more automated equipment, more digital systems, more efficient lighting, more sophisticated control panels and, in some cases, new electrical demands such as EV charging, battery storage or additional production lines. The issue is that not every site’s electrical infrastructure has changed at […]
Read more
