ATEX / DSEAR Case Study 1

Client: BAE Systems

BAE Systems




In 2017 IMS was awarded a series of contracts to facilitate HMNB Portsmouth becoming Dangerous Substance and Explosive Atmosphere (DSEAR) 2002 Compliant. This involved reviewing every room within all 425 buildings within the footprint of the Naval Base and HMS Nelson to identify any Hazardous substances which were in use and any potential sources of release which could lead to a Potentially Explosive Atmosphere being formed.

Scope of Works

Contract No. 1 Stage 1 DSEAR Assessments

  • Identified all Hazardous Substances being used within every room in every building within HMNB Portsmouth
  • Identified quantities of hazardous substances in use and any potential sources of release
  • Evaluated the need for a stage 2 assessment dependent upon findings and available standard models for Hazardous Areas
  • Recorded findings and notified BAE of any areas requiring a detailed Stage 2 DSEAR Assessment

Contract No. 2 Stage 2 DSEAR Assessments

  • The SDS Documentation for the substances in use were referenced with regards to various properties such as; Flammability, Auto-Ignition Temperature and Upper & Lower Flammable limits
  • Sources of release were identified and classified as; Continuous, Primary or Secondary Release
  • Availability of ventilation was classified as; Good, Fair or Poor
  • Using either standard models or computational software the Potential Extent of the Zone/s was calculated as a 3-Dimensional shape
  • Hazardous Area Classification Drawings were completed
  • A Hazardous Area Risk Assessment was completed identifying any remedial actions and procedures to be put in place to reduce the potential for a source of ignition becoming active
  • Identified the need for ATEX Inspections to be carried out
  • Identified the need for in-house training to provide competency for working upon ATEX electrical equipment
  • Identified a need for BAE RP DSEAR to be trained and appointed to oversee ongoing management and compliance

Contract No. 3 DSEAR Electrical Inspections

  • The Hazardous Area Risk Assessment identified that ATEX Electrical inspections had lapsed for a number of years
  • Identified legacy equipment classified prior to DSEAR becoming legislation needed to be risk assessed for suitability for ongoing use
  • Remedial actions were raised for faults found during the inspections
  • An ATEX Electrical Equipment Register was provided to the client to enable them to maintain installed equipment and manage the associated activities

Contract No. 4 DSEAR Remedial Works

  • Due to the findings from the Hazardous Area Classifications and ATEX Inspections various electrical items were replaced throughout the Naval Base
  • Replaced a number of Extraction Systems for DSEAR Compliance
  • Completed a number of Design and Replacement programs for legacy equipment

How we do it

We identified several buildings within the Naval Base which had DSEAR Requirements. Following this identification we completed the relevant documentation to enable BAE to be able to manage their DSEAR Areas and assisted their newly appointed RP DSEAR to create their Explosion Protection Document and Verification Dossier which are requirements under DSEAR.

We assisted them in the implementation of ATEX Electrical Inspections and the schedule required over each 3 year period to remain compliant.


What we have achieved so far

  • We enabled BAE Systems to make HMNB Portsmouth the first DSEAR Compliant Naval Establishment in the country
  • IMS is now the DSEAR Subject Matter Expert (SME) for BAE Systems at HMNB Portsmouth