Hazardous Areas Blog

Site Data

The following Site Data is required:

• Site Owner,
• Site Address.

Environment

The following environmental data is required:

• Historical Maximum and Minimum Temperatures,
• Height above Sea Level,
• Ventilation, in accordance with AS/NZS 60079.10.1:2009 (+A1), for all aspects of the plant to be studied:
  • Natural or Artificial Ventilation,
  • Degree of Ventilation,
  • Availability of Ventilation.

Technical Documentation Required

A Hazardous Area Classification study for a facility with flammable gas and vapour releases requires:

• A defined Scope of Works, reviewed by and agreed with:
  • The Client, and
  • All study participants.
• What Standard or Code is to be applied to the Hazardous Area Classification study,
• Determine what Methodology or Methodologies the client wishes to be used in the study:
• Source of Release by Calculation,
• Source of Release by Example,
• The Generalised Method,
• Risk Assessment for Equipment Protection Levels (EPLs).
• Piping and Instrumentation Diagrams (P&ID) for the areas of the study,
• Process Flow Diagrams (PFD) for the areas of the study, which align with the P&IDs above,
• Pressure Safety Valves (PSV) at their ratings (pressure, mass flow rate),
• Stream Tables which align with the PFDs which nominate the following at every different aspect of the installation (pipe, vessel, vent, junction, drain, sample point, etc) of the study:
• Gas/Vapour types and percentages,
• Temperatures,
• Pressures.
• Mechanical General Arrangement drawings for all the vessels within the scope of the study,
• Diagrams for any network of sumps and/or drains:
• A “single line diagram” of the drainage network,
• Mechanical General Arrangement drawings of all sumps, pits, vessels, relating to drainage,
• Indicate which drains are for separate processes (e.g., effluent, oily water etc.),
• Location and capacity of any “Oily Water Separators”,
• The location and size of any “holding” of “storage” tanks or vessels.
• Photographs of all the vessels, pits and drains within the scope of the study, including:
• 360 degree views of each vessel,
• “Close-up” photographs of each entry, exit and entry into the vessel,
• Photographs of any marking or identifiers on the vessel.
• Pits, sumps, vessels, drains and Oily Water Separators.
• Safety Data Sheets (SDS) for all the materials used within or produced by the process,
• Any previous Risk Assessments for the plant (to assist with EPL nominations),
• Copies of all previous studies conducted, including hazardous area classification drawings,
• Plan and Elevation drawings of the plant.

Safety

Sites with Flammable Gas and Vapour hazards, often have Toxic Hazards as well as Flammable ones. The following information should be supplied, for persons inspecting the site and gathering data:

• A list of all substances, gases or vapours within the areas to be studied which are toxic,
• Nominated PPE (Personal Protective Equipment) required for each area to be studies,
• Relevant Safety Procedures,
• Nomination of Assembly Points in case of a release of toxic gases or vapours.

This material is produced by HAZ. The information is of a general nature only and should not be relied upon.  Each set of circumstances associated with compliance of hazardous areas and Type B compliance is unique and expert advice on your particular circumstances should be sought.  HAZ accepts no liability for any reliance on the information published on this website.