In the previous post, we had talked about hazard control hierarchy. Now we are going to talk about each hazard control method in more detail and show up examples of their implementation.

Hazard Elimination

Hazard elimination is the process of removing the hazards completely from the workplaces. The hazards are not present anymore. That’s why hazard elimination is the most effective method in controlling hazard. Whenever possible use this method to control hazards.

An example of hazard elimination is to design a low-temperature and pressure reaction conditions instead of the high-temperature and pressure condition. High temperature hazard is completely removed and over-pressure condition will no longer exist.

Another example of this is using automatic mode operation rather than manual operation. So that hazards that are associated with manual operation removed to zero level. Elimination of hazards is usually performed at the design or preparation phase and implemented at the source of hazards.

Hazard Reduction

Hazard reduction is the effort to reduce or lessen hazard level from the workplaces to an acceptable level. In this case hazards are still present. It is generally chosen whenever hazard elimination is not feasible.

Hazard reduction is implemented during the design phase and in some cases as a result of evaluation on the existing equipments, jobs, tasks or activities. An example of this is to substitute a hazardous chemical with a less hazardous chemical.

Engineering Control

Including in engineering control are isolation, ventilation, containment and process control. Engineering control deals with the design of workplaces and their related processes.

Isolation of the hazards may come in the form of machine guard, blast shield, welding curtains and hot surface insulation. Exhaust fan that removes catalyst dust and hazardous chemical vapor from a building are examples of hazard control by ventilation, where at the same adds fresh air into that building. Another example of ventilation is fume hood inside the laboratory room.

In case of containment, hazards are enclosed by using enclosed cabs, enclosing noisy equipment, providing a noise-insulated work booth and installation of silencer at the discharge pipe of a compressor.

Process control is the most common hazard control method in chemical plant operation, such as isolation by interlock and safety valve to prevent over pressure.

Administrative control

Administrative control is selected when elimination and substitution is not feasible, and engineering control could not provide adequate control on hazards. Typical examples of administrative controls are provisions of operation procedures, safety signs, safety talks, setting up new safety policies, scheduling working hour to limit exposure to the hazard, implementing job rotation, work permits, alarms and training.

Personal Protective Equipment

Personal protective equipment provides a barrier between workers and the chemical, material, hot surface or noise. As I mentioned in my previous post about personal protective equipment video, it includes respirators, goggles, hand gloves, face shields, hard hat, ear plug and footwear.

Personal protective equipment shall be used when hazard elimination, reduction and engineering control are not feasible, and the administrative control could not provide sufficient additional safety protection.

The above hazard control methods can be applied in combination one with another in order to provide the most effective hazard control.