Five questions
- Does the drawing describe reality? Are the zone boundaries drawn with their extents; is the filling point where the drawing says it is?
- Does the equipment match? Does the marking on every item inside a zone agree with the category, group and temperature class the zone requires? Portable devices count too.
- Were ignition sources assessed? Were all thirteen addressed, or only electricity and flames?
- Were inspections done? Do periodic inspection records exist, and were their findings closed?
- Is the document current? Was it reviewed after the last change — a new line, a new substance, altered ventilation?
The most common finding
The document is well written, the drawing is clean, the classification is right — and the site does not follow the document. A standard luminaire in zone 1, an extension lead run into the zone, a new filling point absent from the drawing. The finding always reads the same: the document and the site do not agree.
Second most common: open findings
Findings recorded in the plant's own inspection records and left open carry serious weight, because they show the risk was known and tolerated. Carrying out an inspection also creates the duty to close what it finds.
How to prepare
The most useful preparation is not reading the document but walking the site with it: drawing in hand, eyes on the equipment labels. That walk surfaces nearly every question an inspector is going to ask.