Hazardous Areas are formally ranked as being a designated hazardous area using the relevant regional or country standards that are directly applicable to the plant design under consideration.
HAZARDOUS FLUIDS (SOURCES)
The relevant regional or country standards will define which fluids are considered as sources requiring area classification. These typically include fluids such as:
• Flammable gas or vapor.
• Flammable liquids which are handled at or above their flashpoint, or which could be heated to the flashpoint after release.
• Flammable liquid that could form a flammable mist.
• Fluids which satisfy the criteria above and which are present periodically within the plant for 100 hours per year or more (e.g. during start-up).
• Unclassified, flammable liquids containing residual, volatile materials and which are stored under confined, heated conditions give rise to limited area classification.