Explosive atmospheres

The topic of Explosive Atmospheres is concerned with the management, design, installation, operation and maintenance of systems that reduce the risk of electrical ignition sources arising from:

  • fixed electrical installations;
  • moveable electrical equipment;
  • lightning in relation to structures with a risk of explosion;
  • electrostatic hazards;
  • radio frequency radiation;
  • isolating joints, for example in cathodic protection systems;

and the mitigation of releases using:

  • flammable and toxic gas detection;
  • fire detection.

The key benchmark technical standards relating to these sub-topics are listed in the EC&I Operational Delivery Guide.

The Dangerous Substances and Explosive Atmospheres Regulations 2002 (DSEAR) require employers to put control measures in place to either remove fire and explosion risks or, where this is not possible, control them. Where explosion risks cannot be removed, electrical sources of ignition should be managed by:

Design of equipment and structures, for example by:

  • the selection of explosion protected (Ex) equipment and/or systems (see pages on ATEX and explosive atmospheres[11]);
  • avoiding hazards due to static electricity by bonding all conductors together and to earth;
  • installing lightning protection systems appropriate to the construction and contents of structures;
  • detuning structures capable of acting as RF antennae in explosive atmospheres within the vulnerable zones of transmitters;
  • application of a protective coating to cathodic protection isolating joints to prevent accidental contact.

Maintenance and inspection of equipment and structures, for example by:

  • initial inspection before plant or equipment is brought into service;
  • ongoing periodic inspection of explosion protected (Ex) equipment and/or systems (see pages on ATEX and explosive atmospheres[12])
  • monitoring of static earthing;
  • maintenance and inspection of lightning protection systems;
  • periodic inspection of above ground isolating joints, for example in cathodic protection systems.

Technical Standards and Guidance

COMAH Competent Authority EC&I Operational Delivery Guide (PDF) [13]

Regulations

Technical Standards

Refer to the COMAH Competent Authority EC&I Operational Delivery Guide (PDF) [17].

Industry Publications

  • Energy Institute[18] Model Code of Safe Practice Part 1: The selection, installation, inspection, and maintenance of electrical and non electrical apparatus in hazardous areas
  • Energy Institute[19] Guidelines for managing inspection of Ex electrical equipment ignition risk in support of IEC 60079-17
  • Energy Institute[20] Model Code of Safe Practice Part 15: Area Classification Code for Installations Handling Flammable Fluids
  • Energy Institute[21] Model Code of Safe Practice Part 21: Guidelines for the control of hazards arising from static electricity
  • EEMUA Publication 186[22] A Practitioner's Handbook for potentially explosive atmospheres.
  • CBI[23] Guidance for Electrical Installation and Equipment within Explosives Manufacturing and Storage Facilities Including Fireworks

HSE Guidance

HSE Operational Guidance

Other information

Link URLs in this page

  1. EC&Ihttps://www.hse.gov.uk/eci/index.htm
  2. Overview - About EC&Ihttps://www.hse.gov.uk/eci/about.htm
  3. Functional safetyhttps://www.hse.gov.uk/eci/functional.htm
  4. Explosive atmosphereshttps://www.hse.gov.uk/eci/explosive.htm
  5. Electrical power systemshttps://www.hse.gov.uk/eci/electrical.htm
  6. COMAH Safety reportshttps://www.hse.gov.uk/eci/reports.htm
  7. Cyber securityhttps://www.hse.gov.uk/eci/cyber-security.htm
  8. Incidentshttps://www.hse.gov.uk/eci/incidents.htm
  9. Resourceshttps://www.hse.gov.uk/eci/resources.htm
  10. Linkshttps://www.hse.gov.uk/eci/links.htm
  11. ATEX and explosive atmosphereshttps://www.hse.gov.uk/fireandexplosion/dsear.htm
  12. ATEX and explosive atmosphereshttps://www.hse.gov.uk/fireandexplosion/dsear.htm
  13. COMAH Competent Authority EC&I Operational Delivery Guidehttps://www.hse.gov.uk/eci/assets/docs/eci-delivery-guide.pdf
  14. Control of Major Accident Hazards Regulationshttps://www.hse.gov.uk/pubns/books/l111.htm
  15. The Management of Health and Safety at Work Regulations 1999http://www.legislation.gov.uk/uksi/1999/3242/contents/made
  16. Dangerous Substances and Explosive Atmospheres Regulationshttps://www.hse.gov.uk/fireandexplosion/dsear.htm
  17. COMAH Competent Authority EC&I Operational Delivery Guidehttps://www.hse.gov.uk/eci/assets/docs/eci-delivery-guide.pdf
  18. Energy Institutehttp://www.energyinst.org/home
  19. Energy Institutehttp://www.energyinst.org/home
  20. Energy Institutehttp://www.energyinst.org/home
  21. Energy Institutehttp://www.energyinst.org/home
  22. EEMUA Publication 186https://www.eemua.org/Products/Publications/Print/EEMUA-Publication-186.aspx
  23. CBIhttp://www.eig2.org.uk/?p=196
  24. Safe use and handling of flammable liquidshttps://www.hse.gov.uk/pubns/books/hsg140.htm
  25. The storage of flammable liquids in containershttps://www.hse.gov.uk/pubns/books/hsg51.htm
  26. The storage of flammable liquids in tankshttps://www.hse.gov.uk/pubns/books/hsg176.htm
  27. Using electric storage batteries safelyhttps://www.hse.gov.uk/pubns/indg139.pdf
  28. Manufacture and storage of explosiveshttps://www.hse.gov.uk/explosives/index.htm
  29. The selection and use of flammable gas detectorshttps://www.hse.gov.uk/pubns/gasdetector.pdf
  30. Dangerous Substances and Explosive Atmospheres Regulations 2002. Approved Code of Practice and guidancehttps://www.hse.gov.uk/pubns/books/l138.htm
  31. OG45 Protection against inadvertent ignition of explosive atmospheres by radio-frequency radiation at onshore hazardous installationshttps://www.hse.gov.uk/foi/internalops/og/og-00045.htm
  32. OG44 Lightning protection at onshore hazardous installationshttps://www.hse.gov.uk/foi/internalops/og/og-00044.htm
  33. Related COMAH Competent Authority Operational Delivery Guideshttps://www.hse.gov.uk/comah/ca-guides.htm
  34. Competencehttps://www.hse.gov.uk/humanfactors/topics/competence.htm
  35. Out of Control, Why Control Systems go wrong and how to prevent failurehttps://www.hse.gov.uk/pubns/books/hsg238.htm
  36. E,C&I Operational Delivery Guidehttps://www.hse.gov.uk/eci/assets/docs/eci-delivery-guide.pdf
  37. Safety Report Assessment Manual (SRAM) Guidehttps://www.hse.gov.uk/comah/assets/docs/s12b.pdf
  38. Linkshttps://www.hse.gov.uk/eci/links.htm
  39. COMAHhttps://www.hse.gov.uk/comah/index.htm
  40. Chemicalshttps://www.hse.gov.uk/chemicals/index.htm
  41. DSEARhttps://www.hse.gov.uk/fireandexplosion/dsear.htm
  42. ATEXhttps://www.hse.gov.uk/fireandexplosion/dsear.htm
  43. Electricityhttps://www.hse.gov.uk/electricity/index.htm
  44. Human factorshttps://www.hse.gov.uk/humanfactors/index.htm
  45. Machineryhttps://www.hse.gov.uk/work-equipment-machinery/index.htm
  46. Explosiveshttps://www.hse.gov.uk/explosives/index.htm
  47. Biosafety and microbiological containmenthttps://www.hse.gov.uk/biosafety/index.htm

Is this page useful?

Updated: 2021-08-26