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EI15 Key Technical Changes

The  4th edition of EI15 includes extensive technical changes from the 3rd edition, the main key technical changes are as follows:

  • Direct examples are now included in Annex D, with the emphasis being placed on the use of the point source approach for area classification.
  • Annex C has been re-ordered and re-structured to aid user understanding.
  • Amendments to the point source approach - amended hazard radii for secondary grade releases from pumps, compressors, flanges and valves (based upon revised equivalent hole sizes); amended hazard radii from pool spills.
  • Guidance and recommendations on equipment design have been removed and incorporated into EI Model Code of Safe Practice Part 1: The selection, installation, inspection, and maintenance of electrical and non electrical apparatus in hazardous areas.
  • Examples on how to assess whether ventilation is 'adequate' are provided.
  • Annexes on protection concepts and fired process heaters have been removed and incorporated into EI Model Code of Safe Practice Part 1: The selection, installation, inspection, and maintenance of electrical and non electrical apparatus in hazardous areas.
  • Amendments to guidance on ventilation of hazardous areas. Amended definition of 'adequate ventilation' and other key findings from HSE Research Report Technical Input on ventilation effectiveness for area classification guidance EI15. Based on this work some sections have been re-structured and sections which are no longer technically valid have been deleted.
  • Guidance on equipment selection and non-electrical sources of ignition has been removed and incorporated into EI Model Code of Safe Practice Part 1: The selection, installation, inspection, and maintenance of electrical and non electrical apparatus in hazardous areas.
  • Incorporation of conclusions in EI Research Report: Dispersion modelling and calculations in support of EI Model Code of Safe Practice Part 15: Area classification code for installations handling flammable fluids, including a sensitivity analysis to various parameters.
  • Incorporation of further background technical information on hazard radii from pool spills.
  • Incorporation of further background technical information on hazardous radii from LPG releases.
  • Revised 'equivalent hole sizes' for frequency bands (LEVEL I - III), based on analysis of the HSE Hydrocarbon Release Database (HCR).
  • Annex F on ventilation and releases within enclosed areas has been expended to include pertinent findings in HSE Research Report: Technical Input on ventilation effectiveness for area classification guidance EI15.
  • Amplification of the discussion of the Limits of Applicability of the Model Code.
  • Amplification of the discussion of Grades of Release, particularly with reference to detection times.