Chronic and acute hazards can be compared to acute and chronic illnesses. A hazard is acute when it's extremely severe, short-term, and dangerous. A chronic hazard, on the other hand, is one that is present over a long period of time.
Chronic hazards are always present, recurring, or habitual. They include the danger of falling if you're a window washer and the danger of hydrogen sulfide (H2S) exposure if you are a worker in an upstream oil or gas worksite.
Acute hazards appear suddenly, like a fallen electrical line, a break in a gas line, or a pressure buildup in a nuclear plant.
Injuries sustained from acute hazards can become chronic medical conditions. For example, a fall as a result of a downed power line can result in chronic back pain. Acute hazards
can also, of course, result in very short-term injuries, such as bruises and
lacerations.
Acute and chronic hazards will be present in every workplace, but managing them will require different approaches. You can plan for and avoid chronic hazards like falls or cluttered floors. Acute hazards, however, are less predictable and require on-the-spot avoidance. Constant checking and preventative maintenance can go a long way to avoiding acute hazards (see Effectively Eliminating Equipment Breakdowns with Total Productive Maintenance to find out what steps you can take to keep your equipment safe). Even with these measures, however, every workplace needs an emergency policy that clearly outlines what to do if workers face an acute hazard.