As you learned earlier, there are many different types of hazards in the workplace. Hazardous conditions include unsafe materials, equipment, the environment, and employees. Unsafe work practices include: allowing untrained workers to perform hazardous tasks, taking unsafe shortcuts, horseplay, or long work schedules. To combat these hazardous conditions and unsafe work practices, control strategies, called the "Hierarchy of Controls" have been developed.
Traditionally, a hierarchy of controls has been used as a means of determining how to implement feasible and effective controls. ANSI Z10-2005, Occupational Health and Safety Management Systems, encourages employers to employ the following five hazard control strategies:
The idea behind this hierarchy is that the control methods at the top of the list are potentially more effective and protective than those at the bottom. Following the hierarchy normally leads to the implementation of inherently safer systems, ones where the risk of illness or injury has been substantially reduced. Let's take a closer look at the hierarchy of control strategies.
Hazard abatement (reduction) measures required to correct a hazard must be technologically and economically feasible (reasonable) for the employer. OSHA uses the following criteria to determine feasibility of engineering and administrative controls:
Elimination and substitution, while most effective at reducing hazards, also tend to be the most difficult to implement in an existing process. If the process is still at the design or development stage, elimination and substitution of hazards may be inexpensive and simple to implement. For an existing process, major changes in equipment and procedures may be required to eliminate or substitute for a hazard.
These strategies are considered first because they have the potential to completely eliminate the hazard, thus greatly reducing the probability of an accident. Redesigning or replacing equipment or machinery may be expensive, but remember, according to the National Safety Council, the average direct and indirect cost of a lost work-time injury is $34,000 and $1,115,000 to close a fatality claim.
Some examples of these two strategies include:
These controls focus on eliminating or reducing the actual source of the hazard. The basic concept behind engineering controls is that, to the extent possible, the work environment and the job itself should be designed to eliminate hazards or reduce exposure to hazards. While this approach is called engineering controls, it does not necessarily mean that an engineer is required to design the control.
Some examples of this strategy include:
When you cannot remove a hazard and cannot replace it with a less hazardous alternative, the next best control is enclosure. Enclosing a hazard usually means that there is no hazard exposure to workers during normal operations. There still will be potential exposure to workers during maintenance operations or if the enclosure system breaks down. For those situations, additional controls such as safe work practices or personal protective equipment (PPE) may be necessary to control exposure.
Some examples of enclosure designs are:
When the potential hazard cannot be removed, replaced, or enclosed, the next best approach is a barrier to exposure or, in the case of air contaminants, local exhaust ventilation to remove the contaminant from the workplace. This engineered control involves potential exposure to the worker even in normal operations. Consequently, it should be used only in conjunction with other types of controls, such as safe work practices designed specifically for the site condition and/or PPE. Examples include:
Administrative controls are aimed at reducing employee exposure to hazards that engineering controls fail to eliminate. Administrative controls work by designing safe work practices into job procedures and adjusting work schedules. Ultimately, effective administrative controls will successfully eliminate the human behaviors that result in 95% of all workplace accidents! Administrative controls are only as effective as the safety management system that supports them. It's always better to eliminate the hazard so that you don't have to rely on management controls that tend to work only as long as employees behave.
Safe work practices may be quite specific or general in their applicability. They may be a very important part of a single job procedure or applicable to many jobs in the workplace. Safe work practices include:
Other safe work practices apply to specific jobs in the workplace and involve specific procedures for accomplishing a job. A training program may be essential if employees are working with highly toxic substances or in dangerous situations.
When a hazard is recognized, the preferred correction or control cannot always be accomplished immediately. However, in virtually all situations, interim measures can be taken to eliminate or reduce worker risk. These can range from taping down wires that pose a tripping hazard to actually shutting down an operation temporarily.
The importance of taking these interim protective actions cannot be overemphasized. There is no way to predict when a hazard will cause serious harm, and no justification to continue exposing workers unnecessarily to risk. By the way, OSHA believes there is always some kind of interim measure that can be used to temporarily abate a hazard.
Using personal protective equipment is a very important safe work practice. It's important to remember that, like other administrative controls, the use of PPE does not control the hazard itself, but rather it merely controls exposure to the hazard by setting up a barrier between the employee and the hazard. Use of PPE may also be appropriate for controlling hazards while engineering controls being installed or work practices developed.
The hierarchy of controls is the standard system of strategies to effectively eliminate workplace hazards. Remember, the first question to ask when considering ways to eliminate a hazard is, "can we apply engineering controls?" You may need to use a combination of strategies to effectively eliminate the hazard. Whatever it takes, do it. You are not just saving a life....you are saving a father, a mother, a son, or a daughter....you are saving a family. It's worth the effort!
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