Explosion Protection Document – EPD

Explosion Protection Document (EPD)

An Explosion Protection Document (EPD) is the single, structured record of how a site prevents and controls explosion risk.

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Explosion Protection Document (EPD) Background and Regulatory Context

ATEX Article 8 requires an EPD that:

  • documents assessed explosion risks,
  • describes the measures adopted, and
  • records the classified zones,

and that it is prepared prior to commencement of work and updated when significant changes occur.

The employer must also classify places into zones and apply the minimum requirements of Annex II; where appropriate, signage is required. Annex I defines gas and dust Zones 0/1/2 and 20/21/22 as the basis for zoning and measures. Annex II sets organisational and technical measures, including training, written instructions, permits to work, and other controls.

Before a hazardous workplace is first used, its overall explosion safety must be verified and maintained over time. In Great Britain, DSEAR imposes parallel duties to assess, control, document, and classify areas where explosive atmospheres may occur.

How EPD Development Works – Step by Step

  1. Scope and Inputs

The work starts by defining what the EPD must cover:

  • Aligning on sites, substances, and boundaries.
  • Gathering drawings, PFDs/P&IDs, layouts, ventilation data, procedures, and maintenance context.
  • Confirming the governing legal framework (ATEX / DSEAR) and the applicable standards set.

This ensures that the EPD reflects the real scope of the site and its obligations.

  1. Hazardous Area Classification

The document then captures the zoning basis:

  • Identifying releases and ventilation conditions and determining Zones 0/1/2 for gases and Zones 20/21/22 for dusts.
  • Sizing extents and recording assumptions in a clear Basis of Classification.
  • Applying IEC 60079-10-1 (gas/vapour) and IEC 60079-10-2 (dust).

Existing HAC work can be incorporated, or classification can be developed as part of the EPD project.

  1. Ignition Source Control

Credible ignition sources and controls are recorded in a structured way:

  • Reviewing ignition sources using EN 1127-1 to frame prevention and protection.
  • Addressing static electricity in line with IEC/TS 60079-32-1.
  • Documenting controls, residual risks, and required procedures in straightforward language.

This provides a clear link between identified sources, measures in place, and any remaining risk.

  1. Equipment Selection and Installation

The EPD also needs to show how equipment choices match the zoning and risk picture:

  • Mapping zones to EPL/category and providing selection notes for engineers and buyers.
  • Interfacing electrical design and installation with IEC 60079-14.
  • Referencing ISO/IEC 80079-36/37 for non-electrical equipment where applicable.

These sections help design, procurement, and maintenance teams keep decisions aligned with ATEX requirements.

  1. Organisational and Technical Measures (Annex II)

Organisational controls are set out in line with ATEX Annex II:

  • Defining training, written instructions, and permit-to-work rules that reflect the EPD findings.
  • Specifying escape, warning, and mitigation measures required by Annex II.
  • Including expectations for signage, housekeeping, and maintenance practices.

This anchors explosion safety in everyday operations, not just in design documents.

  1. Inspection, Maintenance and Lifecycle

The EPD also describes how explosion safety is sustained:

  • Defining inspection and maintenance principles, aligned with IEC 60079-17.
  • Setting revalidation triggers and linking the EPD to Management of Change.
  • Preparing a verification-before-first-use checklist and evidence path.

This ensures that the document remains a living reference, not a one-off exercise.

  1. EPD Assembly and Handover

Finally, all elements are compiled into a single, usable document:

  • A navigable EPD with traceable references and change history.
  • An executive summary for leadership and auditors.
  • Editable registers and a clean action tracker with owners and due dates.
  • Briefings so engineering, operations, and HSE teams share one consistent picture.
RISK management
RISK assessment

Deliverables and Client Value

Deliverables

  • Explosion Protection Document (EPD) with scope, method, and compliance mapping.
  • Area classification drawings and zone schedule with groups, EPL/category, and temperature class.
  • Ignition source register and control measures aligned with EN 1127-1 and IEC/TS 60079-32-1.
  • Equipment selection interface (IEC 60079-14; ISO/IEC 80079-36/37 as needed).
  • Organisational measures pack (training, work instructions, permit-to-work, signage).
  • Verification-before-first-use checklist and revalidation plan.

Our process safety team will support the development or update of your Explosion Protection Document — from defining scope and collating inputs to delivering a clear, compliant EPD ready for internal use and external audit.

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