CompEx Certification

What is CompEx?

CompEx (Competency in Explosive Atmospheres) is an internationally recognized certification scheme that validates the competency of individuals who install, inspect, or maintain equipment in potentially explosive atmospheres (classified into zones).

Key facts:

• Accredited to ISO/IEC 17024 (Personnel Certification)
• Based on IEC 60079 and related standards
• Developed by JTL (formerly EITC) in the UK, now managed by CompEx (a division of JTL)
• Recognized globally by major oil & gas operators, EPCs, and regulatory authorities
• Over 500,000 certificates issued worldwide
• Required or strongly preferred by most oil & gas companies for personnel working in classified areas

Who Needs CompEx?

CompEx is relevant for anyone who works with or around explosion-protected equipment:

Typically Required

• Electricians and instrument technicians installing or maintaining Ex equipment in classified areas
• Inspection engineers conducting periodic inspections per IEC 60079-17
• Commissioning engineers verifying Ex installations before energization
• Maintenance technicians working on Ex motors, junction boxes, control panels

Strongly Recommended

• Design engineers specifying Ex equipment for new projects (Ex14 module)
• Project managers overseeing work in classified areas
• Safety/HSE professionals responsible for hazardous area compliance
• Mechanical engineers working on non-electrical Ex equipment (Ex11 module)

Industry Requirements

CompEx is widely mandated in:

• Oil & Gas — Major operators (Shell, BP, TotalEnergies, Equinor, Saudi Aramco) require or prefer CompEx for contractor personnel
• Chemical processing — Required by many chemical companies for maintenance staff
• Offshore platforms — Often mandatory for all electrical/instrument personnel
• Refineries — Standard requirement for turnaround and maintenance contractors
• Pharmaceutical — Increasingly required where solvent and dust hazards exist

CompEx Modules

CompEx offers multiple certification modules covering different roles and environments:

Foundation Modules (Gas/Vapor)

Dust Modules

Specialist Modules

Awareness

What the Training Covers

CompEx training combines theory and practical assessment. Core modules (Ex01–Ex04) typically cover:

Theory Component

• Principles of explosion protection (fire triangle, explosive limits, ignition sources)
• Zone classification and hazardous area concepts
• Protection methods (Ex d, Ex e, Ex i, Ex p, Ex m, Ex n, Ex t)
• Equipment marking and certification (ATEX, IECEx)
• Gas groups and temperature classes
• Equipment selection criteria
• Relevant standards (IEC 60079-14 for installation, IEC 60079-17 for inspection)
• Cable gland selection and installation
• Earthing and bonding requirements
• Intrinsic safety system design (entity parameters, cable calculations)

Practical Assessment

• Hands-on installation of Ex d (flameproof) equipment including cable glands, torque requirements, and joint assembly
• Installation of Ex e (increased safety) terminal boxes
• Intrinsically safe circuit installation (barrier/isolator connection, cable segregation)
• Inspection exercises per IEC 60079-17 (visual, close, and detailed inspection grades)
• Equipment identification from nameplates
• Fault identification and documentation

Assessments are conducted at approved CompEx centers using real Ex equipment. There is no shortcut — candidates must demonstrate practical competency under observation.

Validity and Renewal

Certificate Validity

• CompEx certificates are valid for 5 years
• After 5 years, renewal is required to maintain certification
• Certificates can be verified online via the CompEx Register

Renewal Process

Renewal requires demonstrating continued competency:

• Option 1: Attend a refresher course (typically 2–3 days) at a CompEx center, followed by reassessment
• Option 2: Some centers offer assessment-only renewal for experienced practitioners with documented ongoing work

Tip: Don't let your certificate lapse. If it expires, you may need to complete the full course again rather than just a refresher.

How to Get CompEx Certified

Step 1: Determine Which Modules You Need

• Electricians: Ex01 + Ex02 (gas), add Ex05 + Ex06 for dust
• Instrument technicians: Ex03 + Ex04 (gas), add Ex07 + Ex08 for dust
• Design engineers: Ex14
• Mechanical engineers: Ex11
• Supervisors: Ex12
• General awareness: Ex F

Step 2: Find a CompEx-Approved Training Center

CompEx centers operate in 40+ countries. Major providers include:

• JTL (UK) — The originating body
• Intertek — Global, multiple locations
• TÜV — Germany and international
• Bureau Veritas — Multiple global locations
• NACE International (now AMPP) — Some locations

Search the CompEx website for centers in your region.

Step 3: Complete the Training

Foundation modules (Ex01/02 or Ex03/04) typically run for 5 days, combining classroom theory and hands-on practical work. The practical component uses real Ex equipment in a workshop setting.

Step 4: Pass the Assessment

Both theory (written exam) and practical (observed hands-on tasks) must be passed. Pass marks and assessment criteria are set by JTL.

Step 5: Receive Your Certificate

Successful candidates receive a CompEx certificate and card, registered on the CompEx online register for employer verification.

Cost and Duration

Costs vary by training center and location. Courses outside the UK may be more expensive due to equipment shipping and instructor travel. Many employers pay for CompEx training as part of professional development.

Prerequisites

CompEx assumes candidates have:

• Relevant trade qualification — Electrical, instrumentation, or mechanical background
• Working experience — Practical experience with electrical/instrumentation installation or maintenance
• Basic understanding of electrical/instrument principles (Ohm's law, circuit fundamentals, instrumentation basics)

There is no strict minimum qualification, but candidates without trade experience will find the practical assessments very challenging. Some centers require proof of relevant qualification or experience before enrollment.

The Ex F (Foundation) module has no prerequisites and is suitable for anyone seeking awareness-level knowledge.

CompEx vs Other Qualifications

CompEx and IECEx CoPC are aligned. CompEx units map to IECEx Units of Competency, and many CompEx holders can obtain IECEx CoPC recognition through a streamlined process.

Career Benefits

For Individuals

• Higher earning potential — CompEx-certified electricians and instrument technicians typically command premium rates, especially offshore
• Global mobility — Recognized internationally; facilitates working in different countries and for different operators
• Job requirement — Many oil & gas positions list CompEx as mandatory or strongly preferred
• Professional credibility — Demonstrates verified, practical competency beyond theoretical knowledge

For Employers

• Regulatory compliance — Demonstrates that personnel are competent per Directive 1999/92/EC requirements
• Reduced risk — Competent personnel make fewer installation errors that could compromise explosion protection
• Contractor qualification — Standard for pre-qualifying electrical/instrument subcontractors
• Insurance — Some insurers recognize CompEx certification as evidence of workforce competency

Tips for Passing CompEx

Before the Course

• Review the fundamentals of explosion protection — fire triangle, zones, protection methods
• Familiarize yourself with Ex markings — you'll need to decode nameplates quickly
• Practice cable gland installation if possible — flameproof cable glands require precise technique
• Review IEC 60079-14 (installation) and IEC 60079-17 (inspection) requirements

During the Course

• Pay close attention to practical demonstrations — the assessment mirrors these exactly
• Ask questions — instructors prefer engaged candidates
• Practice torque specifications for bolts and cable glands — too loose or too tight both fail
• Understand the three inspection grades (visual, close, detailed) and what each covers

Common Failure Points

• Incorrect cable gland assembly (wrong thread engagement, incorrect cable diameter)
• Failure to check flameproof joint condition before assembly
• Incorrect torque application
• Misidentification of equipment markings on nameplates
• Incomplete inspection documentation

Related Topics

• Installation & Inspection — IEC 60079-14 and 60079-17 requirements
• Protection Methods — Understanding every Ex type you'll encounter in training
• How to Read ATEX Nameplate — Essential skill for CompEx assessment
• ATEX for Beginners — Start here if you're new to explosion protection
• Certification Process — How equipment gets certified (complements personnel certification)