What is Safety audit and its relevance?
In any process industry fire due to electrical reasons are very probable, especially in industries
that handle flammable substances. In service industries such as telecom, information technolo-
gy, BPO, consultancy organization, and commercial building such as banks, offices, insurance,
law firms, retail centre etc. Business interruptions due to electrical hazards such as fire in server
room, cable gallery etc. could be quite substantial. Electrical hazards continue to threaten safety
of people and property in the form of shocks, burns, injury, fire & explosion. With electricity
having become indispensable part of our life, electrical risks are to be managed effectively. This
can be achieved by conducting electrical safety audit (ESA) of the installation. Identifying
potential electrical hazards to prevent or minimize loss of life & property is perceived seriously
by many chemical industries the world over. General safety auditing is popular where the
objectives and concepts are quite clear and defined whereas ESA is a specialized area that is
still in the process of evolution.
Electrical safety can be broadly classified and grouped into three categories:
1) Safety related to humans- Human safety audit
2) Safety of equipment- Equipment safety audit
3) Statutory requirement- Statutory audi
t
Human safety audit:
Human safety audit basically covers the safety of human being. Scope of this audit can include
review/checks of:
• Earthing installation of the plant, condition of earthing network its maintenance aspect,
periodic measurement of earth resistance, etc
• Use of earth leakage protection device (ELCB)
• Lightning protection system, static electricity hazards etc
• Grounding of electrical equipment at source & Load end
• Fire fighting and fire alarm system, paging & communication system
• Fire safety of substation building
• Illumination level in operating areas of the plant
• Critical lighting in the event of failure of main supply, lighting at rescue points
• Electrical accidents and near misses in the plant to identify the root cause
Equipment safety audit:
Equipment safety audit involves review/checks of:
• Electrical distribution network & system of the plant with emphasis on protection devices, trip
and alarm setting, interlocks, adequacy of protection provided etc.
Methodology
The field /plant visit is the most important part of the ESA programme. This involves visiting the
plant to identify electrical hazards as per the scope of the audit. In electrical safety audits, the
incoming electrical supply receiving section (outdoor substation and main transformer) is
inspected first. Then the main sub-station housing the PCCs or MCCs and the cable gallery (if
present) is inspected. Next are the electrical equipments installed in various process sections,
the cabling and the distribution transformers located in the plant are visited. The aspects such
as earthing, lightning protection, maintenance condition, loose cabling, temporary wiring,
electrical fire hazards, shock potential, etc. are critically looked-into. The checklist provided in
the ‘Pre-audit Preparation’ section is rather a comprehensive attempt, covering almost all-electri-
cal safety aspects.
The verification of the actual installation against available drawing (such as electrical single line
diagram, earthing lay out, etc.) is also carried out during the field visit.
ELECTRICAL SAFETY AUDITING
With electricity
having become
indispensable part
of our life,
electrical risks are
to be managed
effectively. This
can be achieved
by conducting
electrical safety
audit (ESA) of the
installation.
ENERGY/POWER QUALITY/SAFETY AND ENVIRONMENT SOLUTIONS
10
PROLIANCE ENERGY SOLUTIONS
