Occupational Safety and Hazard Assessment in Steam Boilers

The National Board Inspection Code (NBIC) and Factories and Machinery Act (Malaysia) recognized the potential hazards of steam boilers and established various codes and regulations pertaining to controlling the hazards and minimizing risks. Each year, the authorized inspectors inspect fireside and waterside for defects, scaling, and corrosion. Each year, all essential valves and fittings are dismantled for inspection. Plate thickness is checked, boiler water analysis results are reviewed, and indeed, the authority enforces rigorous maintenance on steam boilers but still, various boiler accidents happened. One might wonder why. The reason lies in one salient factor: human error is the leading cause of boiler accidents. One statistic indicated that 83% of boiler accidents were a direct result of human errors due to lack of knowledge and awareness. Although inspection has become stricter, the local authority does not cover inspection on boiler safety controls and all routine or non-routine activities. OSHA can only provide guidelines for safety in the workplace but ensuring the implementations is beyond their scopes.

The fundamental cause of hazards in an organization is organizational inadequacies. The inadequacies can be related to safety controls, safe operating procedures (SOP), hazard and risk assessment and controls, and training or awareness. With inadequacies, employees usually do not realize the hazards and consequences of their actions. Therefore, to minimize or eliminate risks exposed to all employees, contractors, and visitors in their activities, an organization should establish occupational health and safety (OHS) management system. Only through OHS that hazards can be recognized, and safety and health risks can be assessed and properly addressed. The management can set objectives, provide suitable controls, provide sets of procedures (SOP’s), organize training programs, and establish safety performance evaluation.

Boilers have many potential hazards that must be controlled by safety devices and safe work practice. Before identifying the hazards, one must understand the meaning of hazards. In this context, hazard is defined as “a source or situation with a potential for harm in terms of injury or ill health, damage to property, or a combination of these”. To begin identifying hazards, the management must know what activities are involved. Activities can be divided into two categories which are routine and non-routine. Routine activities include daily operation, chemical preparation, and fuel storage and handling, while non-routine activities include boiler overhaul, confined space entry, and emergency response. The first stage in hazard identification is a selection of job to be analyzed.

The management is to select the key activities first, such as daily operation and chemical preparation. In the second stage, OHS management is to break the activities into logical steps. The logical steps must be unique to the activities, and trivia activities such as switching on lights should be avoided. Examples are taking data from various meters during operation, or pouring boiler chemicals into a jar. In the third stage, the management is to identify hazards and determine the corresponding risks in each step. When preparing boiler chemicals, the boiler operators are exposed to corrosive liquid spill and acid gas release. Risk is the consequence, and in this case, the risks are eyes lesion and pain, burn injury, or cancer if handling hydrazine. High noise level which is above 85 dBA is an example of hazard in daily operation and the risk is obvious, which is deafness. In stage four, the management is to develop risk elimination or reduction measures.

For high noise level, risk elimination or reduction measures would require path noise control such as acoustic insulation (lining) or acoustic partition, enclosure for the noise-radiating source, increase pipe size to reduce steam turbulence, or install noise diffuser. The best approach is to control noise at source, such as installing silencer, changing equipment for example changing normal pressure reducing valve (PRV) to low-noise PRV. Other risk controls for high noise level would be wearing personal protective equipment (PPE) or reducing exposure time. The most common hazard for boiler operation is low water and the risk could be a permanent damage to the boiler or explosion. Modern boilers are usually equipped with automatic level controllers, low water level burner interlocks, low water alarm, and regular checking of gage glasses by the boiler operators. All these are risk controls by safety devices. Working in confined space is a non-routine activity, the hazard associated with it is physical injuries or fatalities due to asphyxia or poisonous gas, and the current risk control is following the guidelines of confined space entry, which shall not be covered here.

In pouring the chemical into a jar, the hazard is chemical splashes to eyes, and the risk is eye lesion and injury. From this, the risk control would be wearing safety goggles. Another example of daily operation is blowing down. Blowdown can cause spillage of hot water, which is the hazard, and may scald boiler operators, which is the risk. The example of risk control is blowing down into the blowdown chamber instead of directly into the atmosphere thereby reducing potential spillage of hot water to the surrounding.

In the final stage, after job safety analysis is completed for each activity, the activities, hazards and risks, and the corresponding risk controls should be documented for reference. Based on that, safe operation procedures can be established to ensure risks at the workplace can be eliminated or minimized. Training must be conducted by the competent person-in-charge to all boiler operators to explain in detail the hazards, risks, controls, procedures and responsibility as well as accountability.

For any organization which does not have structured OHS management system, I would recommend OHSAS 18001 or MS 1722 certification. OHSAS 18001 or MS 1722 provides a set of procedures and tools to promote continual improvement through hazard identification, risk assessment, and control of risk in a very systematic way. Apart from these benefits, I noticed with the implementation of OHSAS 18001 standards, the management and employees in my organization have improved significantly in their understanding of health and safety legislation as well as the ability to demonstrate compliance.

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