Comparison of comparative method.

This is a comparative method comparison chart. These techniques are based on hazard identification by comparing with standards. The various methods are checklist, safety audit, hazard indices and preliminary hazard analysis.

 

Checklist

Safety audit

Hazard indices

Preliminary hazard analysis (PHA)

Purpose

For quick identification of hazards

For ensuring that procedures match design intent.

For identifying relative hazards

For early identification of hazards.

Applicability

In all phases — design construction, commissioning, operation and shutdown.

In all phases of the plant and periodicity .of review depending on the level of hazard.

In design and operation phase used as an early screening technique for fire/ explosion potential.

In preliminary design phase to provide guidance for final design.

Data required

Checklist is prepared from prior experience/ standard procedure manual/ knowledge of system or plant.

Applicable codes and guides, plant flow sheet, P & I diagrams, start-up/ shutdown procedure, emergency control, injury report, testing and inspection report, material properties.

Plot plan of a plant, process flow condition, Fire and Explosion Index Form, Risk Analysis Form, Worksheets.

Plant design criteria, hazardous materials involved and major plant equipment.

Results

Essentially qualitative in nature and leads to “yes-or-no” decision with respect to compliance with the standard procedure set forth.

Qualitative in nature — the inspection teams report deviation from design and planned procedures and recommends additional safety features.

Relative quantitative ranking of plant process units based on degree of risk.

List of hazards (related to available design details) with recommendation to designers to aid hazard reduction