Electrical Safety Audit Why When How Ilovepdf Compressed

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Electrical Safety Audit (ESA) What & When and Why & How of it. For Electrical Risk Management By Dr. A. M. Salsingikar, Ph.D. Chartered Engineer & Accredited Electrical Safety and Energy Auditor

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A) What

& Why of ESA

With electricity having become an indispensable part of our life, electrical risks during operation and maintenance of electrical system are to be managed effectively. Electrical hazards continue to threaten safety of people and property in the form of shocks, injury, burns, fire and explosion. In process industries, fires of electrical origin are very probable, especially while handling flammable chemicals. In service industries such as IT, Telecom sector etc. business interruption losses due to electrical hazards (fire in server room, damage of expensive communication equipment, loss of data, fire in cable gallery, etc.) could be substantial. Identifying potential electrical hazards to prevent or minimize loss of life and property is best perceived through Electrical Safety Audits. Electrical safety audit assists in identifying loop holes & non conformities in the plant electrical system and recommend ways and means to ensure electrical safety. Identified potential electrical hazards during the audit when instantly eliminated or reduced would ensure human and plant safety of human and plant equipment and building. Every installation is required to adopt proper safety measures which can avoid or restrict number of accidents. Electrical safety audit is adopted to effectively establish a sound Safety system in plant. A well conducted audit report will assist management in formulating Emergency Preparedness Plan.

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Safety audits are carried out due to various reasons such as: 1. Statutory requirement (environmental concerns, Risk Analysis for hazardous industries, etc.) 2. Requirement of financial institution (for loans, etc.) 3. Suggestion of an regulatory authorities 4. Process change / plant capacity addition 5. Change of management (Merger / Acquisition) 6. Genuine management concern as a measure of improvement 7. Part of OH& S (Occupational Health & Safety) policy of the organization 8. Major accident in the plant / major accident in the neighboring industry / major accident in a similar industry 9. Requirement of foreign partner Identifying potential electrical hazards to prevent or minimize loss of life and property is best perceived through Electrical Safety Audits. A well planned audit would provide the following benefits: Identification of flaws in the existing safety system. Identification and elimination of safety hazards Improvement of employee morale Improvement of management awareness of problems  Enhancement of employee / employer relations  Premature failures are effectively minimized.  Unexpected outages can be minimized ensuring continues power supply to the end user.  Assisting in the management of Electrical risk    

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Please see a detailed note about Electrical Risk Management in the Annexure Electrical Safety Audit Types: Electrical Safety audit generally falls into the following three main types: • • •

Statutory Audit. Human Safety Audit Equipment Safety Audit. Statutory Audit.

It involves review of the statutory documents for compliance such as: - Govt. Electrical Inspection report - Earth resistance test report of individual earth pit earthing grid network and lightning arrestors. - Statutory clearance for installation of equipment - Provision of electrical shock treatment chart, fire buckets, first aid boxes etc. - Compliance of electrical system with Indian Electricity rules, acts and TAC recommendations - Insulation Resistance of electrical installation - Transformer oil test report - H.T. circuit breaker test report - Protection relay test report

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Preventive Maintenance reports List of Authorized Persons to work on electricity Details of the Licensed electrical contractors engaged. Electrical Single Line diagrams with Name plate details of electrical equipment Staff training in Electrical Safety & First Aid report Electrical Accident report Safe operating procedures & Work Instructions Hazardous Area classification report, if applicable. Human Safety Audit:

• • • • • • •

It involves:

Provision of Earthing of Electrical Equipment Earth leakage protection devices (ELCB's) Lightning protection system and equipments Grounding of electrical equipment as a source Fire fighting and Fire alarm system Protective guards for all rotating equipment Illumination level in various working areas as per standard. Equipment Safety Audit:

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• • •

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It involves:

Schedule of maintenance and calibration of over current, earth fault, overload and other protection relays Insulation Resistance measurement of electrical equipment Critical spares inventory Schedule of measurement of hot spots in switchyard connection, bus-bar joints and equipment connected with non linear loads. Control system voltage measurement, battery, battery chargers and associated sensing devices

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Maintenance schedule of electrical equipment annunciation system.

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Alarm

Main aim of the ES audit is identification and assessment of electrical hazards and offer suitable recommendations for their elimination or minimization. Electrical safety audit thus would help identify potential electrical hazards which when eliminated or reduced, would improve human and plant safety. In general, safety audit examines and assesses all aspects of facility including management’s policy, philosophy, processes, operating procedures, safety organization, documentation, personal protective equipment, equipment protection systems, safety training and motivation. Electrical Safety Audit is conducted to highlight the deficiencies in the present electrical system and to recommend ways and means to ensure electrical safety of the personnel and of plant equipments. The audit can be used to ensure that the plant and its O & M practices match the design intent and construction standards.

Elements of audit: Electrical safety audit basically looks into the details of electrical safety aspects of personnel and equipment prevailing in the plant. It reviews O & M practice followed in the plant, vis-à-vis fault levels. During the process of auditing investigation reports of electrical accidents are studied and commented upon. Electrical safety audit thus would help identify potential electrical hazards which when eliminated or reduced, would improve human and plant safety.

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ESA Programme can be broadly classified into 3 major areas namely: 1. Pre-Audit 2. Audit 3. Post-Audit The efficacy of the audit (identification & control of electrical risks) largely depends on the pre-audit and the post-audit sections. Pre and post audit elements are user / client dependent and obviously the audit depends on the audit team. Unless the ESA objectives are clearly defined and audit recommendations considered, the ESA programme will not be successful. An effective ESA programme should include competent audit team formation, pre-audit briefing, collection & review of relevant information (preventive maintenance documentation, accident reports, electrical inspector’s reports, history cards), discussion with safety & electrical officers, plant visit and then the consolidation to the top management. Main aim of the ES audit is identification and assessment of electrical hazards in the plant and offer suitable recommendations for their elimination or at least minimization.

   

Main Elements of ESA are as under: Application of statutory Provisions of IE Act and IE Rules. Conformance with the relevant IS Specifications and Code of Practice Adequacy of Earthing and bonding in the plant. Condition monitoring of equipment.

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 Hot spots developed and their elimination  Hazardous Area Classification.(If applicable)  Safe Operating practices and documentation of Work instructions.  Effectiveness of PTW  Effectiveness of LOTO system  First Aid training provided.  Identified safety training needs & Safety training provided.  Adequacy of earthing system, ratings of CB and fuses, Relay and Protection system rating of cables and electrical equipments vis-àvis Plant fault levels.  Routine Maintenance and testing done on electrical equipment.  Preventive maintenance practices.  Adequacy of electrical equip and cables commensurate with the Plant fault Levels.  Adequacy of the lightning protection system  Identification of static electricity hazards Review of electrical accidents & preventive measures taken. AUDIT OBJECTIVES (General): - To ensure safety of personnel & property arising due to unforeseen circumstances viz. – fire due to electrical short circuit. - To review electrical system to identify single point of failure that would lead to disruption of process. - To review statutory compliances as regards electrical tests and maintenance. - To determine the effectiveness of the company’s safety and loss prevention measures

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AUDIT OBJECTIVES (Specific): 1. To verify the compliance of statutes through:  Physical inspection of the plant with reference to applicable Indian Standards, Indian Electricity Rules and other relevant codes of Practice.  Identifying electrical hazards (shocks, fires, etc.).  System installations including Protective schemes, classified locations, conductor sizing, transformer sizing, grounding, among others are inspected and compared to the NEC, IE Rules, IS Codes of Practice etc 2.To examine the safety procedures in Operation and Maintenance activities. 3.To suggest ways & means to improve safety performance. Detailed Scope of Electrical Safety Audit: From the foregoing, the scope of Electrical Safety Audit is narrowed down as under:  To discuss with the senior management the purpose of the audit.  To visit the Plant and get the reality check. I take the review of related equipments / products used, consumption, procedures, safety aspects, statutory status, loss records, training needs etc. I also cross verify the details against the historical records maintained in the plant.  To ascertain the importance given to electrical safety in the total safety system.

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B) When of ESA Electrical safety audits should be initiated  Whenever there are capacity additions & major alterations in the electrical system,  If frequent electrical accidents are happening.  Any process change in the plant that may require a re-look at the electrical installations in the changed process section. Periodicity of Electrical Safety Audits • Audit frequency will depend on the nature and type of activities within each area of operation. • A reasonable general guide is that audits be carried out once each year, with more frequent inspections for specific areas or activities. Records of injury and damage accidents should be examined and used to identify high-risk areas and activities and consequently those needing more frequent inspection. • As a general thumb rule, audits by external agencies are carried out every two years and the internal team does the audit every year.

C) How of ESA: Conducting energy audit through electrical safety system audit

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Before undertaking Energy Audit it is necessary to conduct electrical safety system audit of the plant to identify the non conformities in respect of electrical energy utilization. Electrical safety system audit is a diagnostic tool, which is used to assess and evaluate the state of electrical activities in a workplace. It is also used to provide information on the effectiveness of energy loss prevention activities undertaken in the plant and to indicate those areas where action needs to be taken to reduce worker exposures to unidentified hazardous conditions prevailing in the plant machinery and substances. The major objective of this audit is to determine the effectiveness of the plant’s safety and energy loss prevention measures undertaken in the plant. Electrical safety system audit is, thus, a systematic approach to evaluate potential hazards and to recommend suggestions for their mitigation and to identify the effectiveness of the current energy management practices undertaken in the plant. It is an important tool for identifying deterioration of standards, areas of risks or vulnerability, hazards and potential accidents in plants for determining necessary action to minimize hazards and for ensuring that the whole effort is effective & meaningful from the point of view of safety and energy management. The Indian Electricity Rules,1956 and Factories Act, 1948 makes the owner / occupier responsible for providing a safe working environment for the employees. Electrical safety system audit is one method of evaluating the safe environment provided in the plant.

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A well-conducted electrical safety system audit provides the platform to the management to undertake regular energy saving and safety programs. It provides a host of tangible and intangible benefits such as: • Identification and elimination of safety hazards • Improvement of employee morale • Development of a dynamic record of safety performance • Creation of positive cycle of energy conservation. • Improvement of management awareness of problems • Enhancement of employee / employer relations

Audit

Modus operandi: The State-of-the-Art methodology for conducting electrical safety system audit whereby hidden non conformities (NCs) pertaining to activities of plant electrification are first searched and brought to the surface. They are excluded from the scope of energy audit until they are closed by proper rectification process undertaken in the plant. It is rather a prerequisite that the plant electrical system audit be conducted before conducting detailed energy audit. This approach is beneficial as explained below: As a first step towards addressing the issues pertaining to energy management in the plant, it is almost necessary that we first carry out Electrical safety system audit of the plant before undertaking a detailed Energy audit to reveal the

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hidden non conformities in respect of supply and utilization of electric supply. These non conformities are then treated successfully and closed by the client and then we conduct detailed energy audit. This is very important in knowing whether plant electrical system is based on a sound foundation in terms of safety of equipment and personal, adequacy of protection system commensurate with the fault levels etc.

A Word of caution: If an Energy Audit is conducted without identifying the non conformities in the utilization of plant electrical supply through Electrical Safety System Audit then the results and findings of the Energy Audit will not be fruitful but in fact, they will be misleading and unreliable and will be difficult to implement.

General Scope of Electrical Safety System Audit: A)Hold an Opening meeting with the plant senior management to discuss the aims of the audit and our modus operandi. B)Visit the Plant and get the reality check. During this visit we take the review of related equipments / products used, energy consumption, procedures, safety aspects, statutory status, loss records, training needs etc. We also cross verify the details against the historical records maintained in the plant. C)Identify the main energy consuming areas/plant items and to collect data on plant energy resources & major energy consuming centers.

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Specifically carry out the following reviews: 1. Electrical System installations are reviewed for the Statutory Compliance in respect of the Protective schemes, classified locations, conductor sizing, transformer sizing, grounding, and many other items are inspected and compared to the NEC, IE Rules, IS Codes of practice etc. 2. Physical inspection to identify electrical hazards. 3. Review of plant lightning protection system (need, adequacy, installation and maintenance) 4. Identification of static electricity hazards in the plant operations 5. Review of electrical accidents and near misses in the plant to identify the root causes of trouble. 6. Review of electrical systems & procedures (work permits, interlocks, lockout tags, etc.) 7. Cable audit: A)Assessing the integrity of insulation of cables by carrying out insulation resistance tests. B)Verification of insulation strength, capacity, and actual load on cables. C)Verification of joints in between and end terminations 8. Review of the earthing system (installation & maintenance aspects) in the plant based on IS 3043.

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9. Identify areas of overloading by carrying out load current measurements and comparing against transformer capacity and cable current carrying capacity calculation 10. Review of protection devices and systems provided in the electrical installation. 11. Review of existing short circuit fault levels vis-à-vis the adequacy of existing earthing system, circuit breaking capacity of fuses and circuit breakers and relay settings. 12. Review of adequacy of the capacities of the transformers, cables, motors, etc. based on actual load current measurements and cable current carrying capacities. 13. Review of the hazardous area classification carried out in the plant as per IS: 5572 and to review the selection, installation of special electrical equipment as per IS: 5571 ( if applicable). 14. Review the EPM (Electrical Preventive Maintenance) programme in the plant and to examine the documentation, checklists, work permit, test records, etc. 15. Review of the plant earthing system installation layout and its maintenance. 16. Review the identified safety training needs of the plant employees. 17. Review of record of hot spots developed and their elimination 18. Review of the following test records, evaluating the test results and to suggest recommendations as per applicable standards. a. Transformer oil test.

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b. Insulation Resistance Tests. c. Earth Resistance tests. 19. Review the importance given to electrical safety in the total safety system In general, safety audit examines and assesses all aspects of facility including management’s policy, philosophy, processes, operating procedures, safety organization, documentation, personal protective equipment, equipment protection systems, safety training and motivation. It thus involves identification and assessment of electrical hazards and offer suitable recommendations for their elimination or minimization.

Audit Process 1.Electrical safety audit is accomplished in a logical series of steps starting at the plant or facility. 2.Perform a series of onsite interviews with operations, maintenance & safety personnel to determine the existence and availability of procedures, documentation, safety training, safety equipment, and other such critical safety-related items. 3. Management and employee questionnaires are administered for audit analysis. 4. A physical walk-through is performed to inspect all electrical system and equipment. This activity takes about three days depending upon the plant size. The walk-through is documented with digital photographs.

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5. The visit ends up in an exit meeting at which time provide an overview of the findings including any life threatening hazards and code violations. The audio-visual presentation is made in this meeting. 6. There after produce a detailed, comprehensive report which documents all of our findings and includes our recommendations for improving your electrical-safety program. To sum up, help the client to manage the electrical hazard risks effectively by assisting in developing the safety culture in the plant through electrical safety audit, electrical system studies and the electrical safety training at his door steps. Electrical Safety Audit Questionnaire The questionnaire is a vital tool for successful inspection and time spent on its preparation is as valuable as that taken by the audit itself. Auditing experience will reveal the need for supplementing or modifying it, provided that the auditors adopt a flexible approach to their task, and the danger of confining attention only to those matters listed in the original questionnaire must be avoided. The details that would help the audit team (especially in case of external audit) will be included in the pre-audit questionnaire. Although the generic details will be made available to the audit agency in the initial stages, the specific details would help the team to prepare themselves to carry out the safety audit in an efficient manner. The pre-audit questionnaire for ESA could include the following aspects: •

Process details

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Electrical Single Line Diagram

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Name plate details of major electrical equipment

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Details of classified zones in the plant

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Details of flammable chemicals handled in the plant

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Details of electrical accidents in the plant

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Details of addition / expansion of the plant including electrical installation Overview of electrical maintenance system

ESA checklists Checklists can be made with reference to: •

Statutory Regulations

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Non-Statutory Standards (national and international)

It could be prepared based on various applicable statutory and nonstatutory standards and codes of practice. Good engineering practice found during other ES audits in similar installations can also be included in the checklists. International standards such as IEEE and NFPA can also referred wherever found necessary. Another important aspect in referring to various standards is the possible confusion in reconciling a safety recommendation. The factors listed below are to be considered while suggesting a recommendation, if contradicting statements are mentioned in rules / standards. •

Compliance to statutory requirements

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Safety of the people and the plant

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Non-Statutory Standards (national and international)

The experience gained by the ESA team members is a very crucial factor in the compilation of audit checklists. Experienced and competent team members can offer many practical, cost-effective safety suggestions and solutions. The checklists could contain the following sections for specific checks: Grouping the observations in the following manner helps to identify and evaluate the areas of concern. Another way of categorization is having the checkpoints grouped under various plant sections / areas, which is the popular method. An advantage of this popular method is that a process section / unit in-charge can be asked to comply with the recommendations by giving a copy of the report section to him. But for the management to understand the efficacy of the various electrical safety elements, the grouping as indicated below will be of use. This way of grouping enables the consolidation exercise more effective.

A few important matters: With the company’s consent, opening meeting will be held to explain the methodology of ESA. The client is free to invite the participants from its organization to get acquainted with ESA. 1 To formulate ESA team for client’s representation in ESA. 2 The review of the existing entire electrical and lightning protection systems in the premises by visiting the facility as per the applicable Indian electricity acts & rules, various standards e.g. IS: 2309, IS 5216 and

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NFPA 780 and recommending corrective measures wherever necessary. The digital snaps of the unsafe conditions will be taken with prior Management approval. 3 Generally in ESAs, the main areas are sub-station, main power transformer, distribution transformers, Power Control Center room, Motor Control Center, Lighting panel, Distribution Boards, critical motors, D.G. sets, general condition of electrical cabling and wiring, etc. are inspected.

Do This i) At the outset, there will be an Opening meeting with Heads of Departments and other Senior Executives. ii) Study of relevant documents such as those pertaining to safety procedures & systems in the Areas/Sub-areas covered under the Scope. iii) Discussions/Interviews with key personnel at various levels. iv) Physical inspections of plant & conducting necessary tests in the presence of plant engineer. v) On the last day of our visit there will be a Closing meeting with the senior executives along with a powerpoint presentation of our major findings and critical observations. vi) Draft & Final Report submission.

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Deliverables A detailed well-written report containing audit findings and the recommendations in compliance with approved practices like Indian Electricity Acts & Rules, National Electrical Code, and NFPA 780 & IS 2309, IS 5216 etc. will be submitted within 3 weeks to improve electrical safety. A soft copy of the draft to be submitted for client’s comments. a) Submission of a Draft audit Report on the audit findings (in soft copy form) containing specific observations in respect of the following: 1. Condition of the Installed electrical equipment and wiring systems.

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