Class societies and flag states require ongoing inspection to confirm that installations continue to meet their original certification. Periodic tests include:
Insulation resistance of cables and terminations
Verification of seals on Ex d and Ex e enclosures
Surface temperature measurement of luminaires and motors
Ventilation flow rate and pressure differential checks
Gas detector calibration and functional testing
Records are maintained under the ship's Safety Management System (SMS) and reviewed during audits and port state inspections. Any modification to layout, equipment, or ventilation triggers a Management of Change (MOC) procedure, requiring re-assessment of zone boundaries and updates to hazardous area drawings. As-built documentation must reflect reality – discrepancies between design intent and installed condition are a common finding during audits.
Training ensures that crew and contractors understand where zones begin and end, which tools are permitted, and how to respond if gas is detected.
Not all hazardous areas are permanent. Tank entry, cargo transfer upset conditions, or maintenance activities can create temporary Zone 0 conditions in normally safe spaces. Gas-freeing procedures, continuous monitoring, and controlled access prevent incidents during these operations. Understanding that zone boundaries can shift with operational state is as important as knowing the static classification.
Hazardous Area Classification is a detailed engineering map that supports safety across the entire lifecycle of an offshore structure. By applying standards such as IEC 60092-502 (2nd edition, 2024), IEC 60079-10-1, IMO SOLAS, and the IGC/IBC Codes, designers and operators control ignition risk even in the harshest marine environments.
About us
