Five years is a limit, not a default: Competence renewal in hazardous areas

CompEx HazardEx Article – July 2026

Training and competence assessment are an important part of hazardous area safety. Certificates of competency provide evidence that an individual has been assessed against a recognised standard and; at the point of assessment, demonstrated the required level of knowledge and skill. However, certificates are sometimes treated as though they provide assurance for the full duration of their validity without further thought. This article challenges that assumption.

For CompEx, the maximum renewal period is five years. This is aligned with the maximum reassessment period reflected in Annex B of IEC 60079-17, which provides guidance on the competence of personnel involved in inspection and maintenance activities. However, the important word is “maximum”. A five-year certificate should not automatically be interpreted as the correct renewal interval for every person, role, site, or employer.

This distinction has been brought into focus through a recent LinkedIn article and discussion of regulatory requirements in Kazakhstan. Order No. 22-н/қ of the Minister of Energy of the Republic of Kazakhstan, dated 17 January 2025, revised clause 596 of the Rules for Technical Operation of Consumer Electrical Installations. The revised clause states that the frequency of training of personnel admitted to work in explosive atmospheres and on explosion protected electrical equipment shall not exceed three years.

This does not mean every system should adopt a three-year renewal period. Similarly, it does not undermine the five-year model used by CompEx and other schemes. The real question here is not simply: “Is the certificate still in date?” A better question is: “Is this person still competent for the work we are asking them to do?”

This view is also consistent with the wider accreditation context. UKAS RG101; which supports accreditation for the inspection of electrical equipment and installations in hazardous areas, reinforces the importance of competence within formal inspection activities. Its relevance is not that it sets a personnel renewal period, but that it places competence within an assurance framework. In hazardous area work, a recognised certificate is an important part of that framework, but it should sit alongside supervision, technical review, CPD, audit findings and evidence of recent (often safety critical) task exposure.

This position is supported by recent competence-retention research. Cahillane, Anderson, MacLean and Smy describe skill decay as the failure to retrieve knowledge and skills after a period of non-use. Their work also highlights that knowledge and different types of skill do not necessarily decay at the same rate. In practical terms, refresher training and recertification should not be driven solely by a fixed calendar interval. It should be informed by the task being performed, how often that task is practised and the consequences if it is performed incorrectly.

That is highly relevant to hazardous area work. Ex competence is not a single, simple skill, nor is it limited only to electrical equipment. Electrical and non-electrical equipment can both present potential ignition sources if they are incorrectly selected, installed, inspected, maintained or repaired. Competence therefore combines technical knowledge, practical application, procedural or engineering judgement and decision-making across the full range of equipment and activities that may affect explosion safety.

For an individual who works regularly in hazardous areas, a five-year renewal period may be entirely reasonable. A technician who routinely installs, inspects, or maintains Ex equipment is continually applying their knowledge and skills. If this is supported by effective supervision, audit, technical support and updates, and continuing professional development, there may be good evidence that their competence is being maintained between formal reassessments.

The position may be very different for someone who only works infrequently in hazardous areas. An individual may hold a valid certificate but spend long periods working outside Ex environments. They may not regularly apply the principles associated with the Types of Protection, nor conduct activities associated with equipment selection, installation, inspection, or maintenance. If they also have limited access to CPD, mentoring or technical support, the risk of knowledge and skills fade increases.

This is not an intended criticism of the individual. It is, more often, a foreseeable competence management issue. If a task is complex, safety-critical, and infrequently practised, the employer should not assume competence remains consistent simply because the certificate remains valid. An incorrectly selected cable gland, a missed inspection defect, an overlooked mechanical ignition hazard or a misunderstanding of equipment marking may not create an immediate incident. Instead, the weakness may remain hidden until the equipment is exposed to conditions where ignition prevention measures are relied upon.4

The Competence Retention Analysis Technique, or CRA-T, discussed by Cahillane et al, provides a useful way of thinking about this issue. Although developed in a defence context, its underlying principle is transferable: tasks can be broken down into different knowledge and skill components, and those components may have different retention characteristics. It also encourages consideration of task frequency and criticality when determining refresher training priorities.

Employers do not need a complicated model to make better decisions. They can start by asking practical questions. How often does the individual perform hazardous area work? What type of work do they undertake? How complex are the installations? What level of supervision is provided? Have there been recurring defects or audit findings? Have standards, site procedures or equipment types changed? Is there evidence of CPD or observed practice?

Importantly, this does not always mean repeating a full qualification early. Employers can use a range of measures to maintain confidence, including refresher training, toolbox talks, targeted reassessment, CPD records, mentoring, technical briefings, workplace observation, and internal verification. The aim should be to maintain competence continuously, not simply wait for the certificate expiry date.
The same principle already applies elsewhere in hazardous area management. Inspection intervals should not be arbitrary; they should reflect the environment, equipment type, deterioration mechanisms, previous findings, and risk. Competence should be managed with the same level of care.

Individuals also have a role to play. Holding a certificate should not be seen as the end of learning. Those working in hazardous areas should be encouraged to recognise their own limitations, seek support when undertaking unfamiliar work and maintain their professional development throughout the life of their certificate.1The maximum five-year CompEx renewal period remains a valuable and practical framework. It supports consistency, portability, and international recognition. But it should not become the path of least resistance. Employers who default to five years without considering exposure, task risk and competence retention may be relying on assumption rather than evidence.

A certificate has an expiry date. Competence does not.

References:
1. UKAS RG101. Accreditation for the inspection of electrical equipment and installations in potentially explosive atmospheres. Edition 3, September 2024.

2. Cahillane, M., Anderson, T., MacLean, P., and Smy, V. (2025). Competence Retention Analysis: A Technique for Predicting and Managing Retention Within Organizational Training Design and Delivery. Journal of Cognitive Engineering and Decision Making.