Preventing Accidents

According to data from the Ministry of Labour and Employment, 3,562 workers died in factory accidents across India between 2014 and 2016, and more than 51,000 were injured in that period. This works out to an average of three deaths and 47 injuries every single day. A 2017 study by the British Safety Council painted an even bleaker picture: 48,000 workers die of occupational accidents every year in India, of which 24 per cent is in the construction industry.

Policy and regulation

Based on the provisions under Section 53 of the Electricity Act, 2003, the Central Electricity Authority (CEA) framed the safety regulations, the Central Electricity Authority (Measures relating to Safety and Electric Supply) Regulations, 2010, and subsequent amendment, the Central Electricity Authority (Measures Relating to Safety and Electric Supply) Amendment Regulations, 2015. These are applicable to all electrical installations in the country.

Under Section 162 of the Electricity Act, 2003, the central/state governments have their own electrical inspectorates to enforce the specified safety regulations in electrical installations belonging to or under the control of their respective jurisdictions. In case of electrical accidents, the appointed chief electrical inspectors/electrical inspectors conduct enquiries on a case-by-case basis and suggest remedial measures for the prevention of such accidents.

Following the blast in the boiler section at the 500 MW Unit 6 of NTPC Limited’s Feroze Gandhi Unchahar Thermal Power Station in Uttar Pradesh in November 2017, the Ministry of Power had set up a committee to investigate the cause of the blast and suggest remedial measures. For a similar purpose, another committee was constituted by the Department of Heavy Industries, Ministry of Heavy Industries and Public Enterprises. Based on the recommendations of the committees for safe operations of thermal power plants (TPPs), the CEA issued an advisory to all TPPs in the country in January 2019. The key recommendations to be followed by power utilities as per the advisory are as follows:

  • All systems and facilities including control and instrumentation(C&I), control loops, wall soot blowers and long retraceable soot blowers should be completed before the commissioning of the unit/plant.
  • The ash handling capacity of the bottom ash handling system, the economiser ash handling system, the air preheater ash handling system and the electrostatic precipitator for a fly ash handling system should be designed keeping in view the likely maximum ash content of coal.
  • Water injection for dislodging ash build-up over the furnace bottom should be avoided. However, if water jetting is necessary, it should be undertaken without compromising on stable combustion conditions inside the boiler.
  • The standard operating procedures/ local management instructions of the plant should be periodically reviewed. Further, the plant’s operating guidelines should be in line with the original equipment manufacturer’s recommendations. The permit system of undertaking operations and maintenance (O&M) activities should be endorsed by the safety department, in addition to the O&M department.
  • No maintenance work should be undertaken when the boiler is in operation. Besides, proper communication regarding maintenance work should be made to avoid any risky operations.
  • The persons working in the ash handling area should be provided with thermal wear, which can withstand high temperatures. Flame-proof clothing should be provided to people working near the furnace area.
  • The plant engineers deployed at different levels should have adequate and relevant experience.
  • The control room logbooks should be filled in a proper manner, indicating the prevailing status of key unit parameters, operating parameters of major equipment/systems and shift activities in a chronological order.

Safety in power generation

Enhancing plant safety saves money for the utility by reducing medical expenditure and workers’ compensation insurance costs, and adds value to its business by improving work efficiency and productivity.

The keys to successful plant management are identifying who is the centre of the entire plant safety management, ensuring appropriate and timely documentation as well as record-keeping, and knowledge sharing involving all levels of the plant workforce from management to workers. Further, protecting people on the job is in the best interest of the plant owner. Enhancement of plant safety will add value to the plant by uprating work efficiency and improving plant economy, which will help the utility build a good reputation in the sector.

In a large power plant, electrical systems covering voltages right from 110 V to 400 kV are distributed in a complex network. Thus, in a power generation environment particularly, the chances of electrocutions are high. Electrical current can damage or destroy property and seriously injure anyone in close proximity. Electrical flashover is a common kind of accident that disturbs the smooth running of systems. Many workers are injured and killed every year while working on energised equipment. Those who work with or near electrical current on a regular basis need safety training to protect themselves and their co-workers. With proper training, electrical workers can learn vital hands-on skills and complete their duties efficiently and safely. These skills will help them to:

  • Understand which (PPE) personal protective equipment is appropriate for each job and the proper way to use this equipment
  • Recognise the signs of potential danger and the safety steps to take
  • Safely perform repairs and maintenance in areas with high voltage
  • Avoid serious accidents that could cost lives, or millions of rupees in equipment, product or output
  • Learn about official safety standards, recommendations and guidelines related to work

Meanwhile, employers can use the following techniques to ensure that their employees carry out their everyday work in the safest manner possible:

  • Keep an inventory of PPE and other safety equipment.
  • Establish a periodic inspection routine.
  • Promptly repair or replace any damaged or lost equipment.
  • Hold weekly safety meetings to remind workers of proper procedures and acceptable actions.
  • Use some of the time to review recent accidents and discuss ways to avoid them in the future.
  • Follow the labour and safety codes set by the government, and ensure that workers are aware of these statutes.
  • Make a plan to respond to emergencies. Post the plan in writing and review it periodically with your workers to ensure they are ready in case of any emergency.

The best way for employers to protect their electrical workers is to give them the knowledge they need. There are several publications and training modules available in India on PPE, tools, and other important topics related to power generation. For example, the National Safety Council comes out with publications on industrial and power plant safety, while the National Power Training Institute (under the power ministry) conducts such training programmes.

Some design-related safety measures that can be incorporated include making sure that the bus bars in the switchgear, motor control centres (MCC) and panel boards are insulated so as to reduce the arc fault and also to help in the self-extinction of arc fires. Further, current-limiting devices such as fuses and circuit breakers may be used instead of current-protective devices. Splitting of large load, single distribution boards to different independent sections can be done to limit fault current. For high capacity LT motor feeders, dual element fuses can be used. Also, the use of residual earth leakage, circuit breakers in low voltage circuits, particularly in welding supply sources, can be promoted.

For NTPC, the country’s largest power generator, health and safety are key priorities. There is a three-tier structure for occupational health and safety management at stations/projects, at regional headquarters and at the corporate centre. The business unit head and senior management carry out regular plant inspection and review. Internal safety audits of all project sites by their own safety officers as well as external safety auditors are regularly carried out and complied with. Cross-functional safety task forces are functional at all projects and stations to monitor the unsafe working conditions and rectify them accordingly. Effective engineering controls are provided at all operating stations to indicate and handle on-site emergencies. Detailed emergency plans have been developed and responsibilities assigned to each concerned to handle such situations. Mock drills are also conducted regularly to check the “healthiness” of the system.

Emerging areas for safety concern

Significant importance is accorded to electrical safety, and as many as 15 reasons that result in electrical short circuits have been identified. Some of these are loose connections in wiring, the usage of electrical heating elements in industries, faults in air conditioners, and the use of PVC cables and inverters.

In order to ensure the safety of users against the hazards of electric leakage, the private power utility of Delhi, Tata Power Delhi Distribution Limited (TPDDL), and Havells India signed an MoU to strengthen the distribution of earth leakage circuit breaker (ELCB) devices in the north and north-western parts of the capital. Typically, deploying miniature circuit breakers (MCBs) is the most common practice that is followed for protecting electrical devices from short circuits and overload. However, MCBs do not ensure safety of the users when it comes to current leakage. Thus, for guaranteeing human safety from current leakage, it is extremely crucial to install earth leakage circuit breakers (ELCBs).

Another growing concern for utilities is the trend of consumers feeding the generated power from renewable energy sources and micro-scale generator units into the grid. Several utilities have warned that power injection in the distribution grid by mass-scale distributed generators may lead to electrocution primarily because of the lack of proper safety features. To overcome this, the CEA guidelines recommend the installation of intelligent grid-tie inverters (GTIs) with solar PV. This can help in providing power to consumers and also in feeding excess electricity generated in solar PV plants into the grid. GTIs automatically stop back-feeding of electricity generated in solar PV plants and prevent accidents in the grid. In such conditions, power will not be available on the consumers’ premises.

In case consumers want to use the solar PV power at the time of grid failure, they can install an automatic switching system to isolate the battery system supply safely from the grid. Another important area with regard to safety pertains to electric vehicle (EV) charging stations. Given the proliferation of EVs, the CEA issued safety regulations for AC and DC charging stations in June 2019, in line with the International Electrotechnical Commission (IEC) standards. These regulations specify the provisions for earth protection systems, protective devices required, provisions for preventing fires, testing of charging stations, inspection, etc.

Utilities are also concerned about the sharing of common corridors by electric power transmission lines and pipelines, which are becoming more commonplace. Such corridor sharing can result in undesired coupling of electromagnetic energy from the power lines to the paralleling facilities. The principal concerns are with respect to both personnel safety and equipment operational compatibility. Induced interfering voltages and currents can result from either magnetic or electrostatic induction from the power line circuits. The induction can occur during either the normal steady state operation of the power system or during a fault.

Conclusion

The first step towards developing a safe work environment is to have procedures in place that provide guidelines for employees to perform various tasks safely. Devastating accidents have been taking place even though India currently has 13 labour laws, including the Factories Act, 1948; the Mines Act, 1952; and the Contract Labour (Regulation and Abolition) Act, 1970, for dealing with the safety, health and working conditions of workers in various industries. In 2018, the central government proposed a L.C. Bill to merge these 13 laws into a single labour code. The Occupational Safety, Health [OSH] and Working Conditions Code was introduced in the Lok Sabha in July 2019.

The OSH Code applies to establishments employing at least 10 workers, and to all mines and docks. It also provides special provisions for certain types of establishments and classes of employees, such as in factories, mines, and building and construction. The code proposes one registration, one licence and one tax return instead of multiple registrations, licences and returns as required in the existing 13 labour laws.

However, the amalgamation of well-intentioned laws on paper alone cannot reduce the number of industrial accidents on the ground, unless the norms laid down in the laws are followed and implemented. And, on that front, Indian industries have been extremely lax.

In January 2018, after 17 workers died in a fire in Delhi’s cramped Bawana industrial area, it was found that their factory had just two fire extinguishers, one exit gate and no fire evacuation plan. Worse, the building was illegally being used as a warehouse for firecrackers. Also, across the industrial area, operational licences had been granted to factories without adequate inspection of their safety measures.

The problem is compounded by the shortage of inspection staff. A study by the British Safety Council found that India had just one inspector for every 506 registered factories. For too long, Indian industry has been lax about following safety norms. The media has also exposed the safety violations by the management of several industries. Accidents have been reported in pharma and chemical manufacturing units at regular intervals for the past few years, claiming the lives of workers in these units.

Net, net, electrical accidents have long been recognised as a serious workplace hazard, with employees exposed to electric shocks, electrocution, burns, fires and even explosions. These can be prevented through safe work practices. To this end, a good safety and health programme can prevent and control electrical hazards. n

Anita Khuller

(With inputs from Down To Earth and other media)