The correct terminology is important when it comes to workplace safety. For example, it is easy to refer to “hazards” when you really mean “risk”. And the other way round. Hazards need to be identified, and risks need to be mitigated. So, what is the difference exactly?
Hazards
Hazards refer to sources of potential damage or harm. They can take many forms including:
- substances (dangerous chemicals),
- energy (electricity or pressure),
- conditions (loose materials), or
- process conditions (extreme temperatures).
Hazards might also include energy sources (falling from a height, contact with live power sources or collisions between moving objects). Dangerous materials (infectious organisms), certain behaviours (running in the plant) or activities (welding, cutting, digging) are all real-factory examples of hazards.
It is important to emphasise that hazards refer to potential damage or harm. A well-controlled process might involve many hazards but be perfectly safe provided it is operated correctly. However non routine work like maintenance is often necessary, requiring a system to control this work safely. In designing a safe control of work work system, it is vital first to identify any hazards and then to manage the various methods, controls, and practices to minimise the potential of any harm.
Hazards remain hazards independent of whether the work is routine in nature or occasional (such as maintenance).
Risks
On the other hand, risk refers to the probability of significant damage or harm resulting from hazards.
Risk is a combined measure of the likelihood of any damage or harm, together with the consequences.
Sometimes likelihood and consequences work together; that is, the likelihood is high, and the consequences are severe. In this case, the risk is also very high. Or, if the likelihood is low and the consequences low, then the overall risk is low. In between these extremes are more interesting combinations where the likelihood might be low, and the consequences very high (for example, a nuclear plant explosion), or the likelihood is high and the consequences relatively low (for example, slipping on a wet floor).
Sometimes the likelihood and consequence are assigned numeric values that are multiplied together to determine the overall risk score, and attention is focused on the highest risks. However, this practice can be flawed when assessing safety risks. In general, responsible companies will not accept any level of safety risk. The goal is zero harm. Therefore, all safety risk needs to be mitigated as far as reasonably practical.
Hazard risk assessment
Identifying hazards and separately determining the risk are fundamental steps in a safe system of work. A risk assessment (sometimes called a hazard risk assessment) is the process by which all hazards are identified, and the related risk factors then determined. These risk assessments are best done by an experienced person who is very familiar with the conditions in the workplace. The risk assessment system should ensure an objective, practical and accurate assessment of actual risk, in order to select appropriate controls to make the work safe.
Controls and precautions
Safety-related risks are mitigated (reduced) by implementing controls. For example, the hazard of high voltage electricity might lead to severe electrical shock when working on live equipment. As a control measure, the equipment must be isolated before work can start. In addition, the technician needs to double-check for any voltage present before touching any potentially live components.
In practical scenarios when working in industrial plants, no matter how many controls are in place, the residual risk is never zero. Human error, faulty equipment, the wrong tools, bypassing procedures can all contribute to elevating the risk and causing an unexpected and serious accident. Implementing backup control measures such as a standby (or brother’s keeper), emergency response plan and so on are also essential to keep the overall risk as low as possible.
Barriers
“Barriers” can sometimes be a more complete approach to mitigating risk by considering both how to prevent unwanted events (what controls to use) and also how to limit the consequences.
Suitable barriers around a hazard need to include preventative controls (for example, proper isolation) and reactive controls (for example, ensuring an emergency earth leakage trip is in place and a power shut down procedure is in place).
The permit to work and workplace/job risk assessment
When potentially dangerous work is done on the plant, the hazards need to be identified, and all controls put in place to protect against unwanted events.
This procedure (for control of work) is often managed using a permit to work. However, the permit to work is only part of the solution. Before actual work starts, it is also necessary to inspect the job site for any new hazards that might not be shown on the permit. For example, heavy machinery related to another job might be temporarily operating in the same physical space. These job site risk assessments are a critical part of a safe work procedure. The site risk assessments are often referred to as “job risk assessments” or “point of work risk assessments”.
Hazards, barriers, and other elements identified on the permit together with those identified during the job risk assessment must also be carefully checked to ensure consistency.
For example, personal protective equipment specified on the permit might have unintended consequences and introduce an entirely new and different risk when evaluating the job risk at the site.
An example might be the requirement for a mask specified on the permit for the dust hazard. When inspecting the site the dust hazard is subsequently judged to be very severe and therefore requires proper breathing apparatus. A mask and breathing apparatus are not worn together.
A complete integrated electronic system that controls both the permit to work and the job risk assessment is therefore essential to manage this scenario safely. This integrated system will ensure consistency and ensure that accurate information about precautions, controls and barriers is readily available to all members of the working party and all other people potentially affected.
For more information on how IntelliPERMIT and OpSUITE can help you better manage your process safety please contact the team at Adapt IT.