Hazard and risk are different things
Two words sit at the center of workplace safety, and they are often confused. A hazard is something with the potential to cause harm: a live electrical conductor, a flammable liquid, a heavy suspended load, a slippery surface. Risk is the combination of how likely that harm is and how serious it could be.
A hazard can exist with very little risk if it is well controlled or if nobody is near it. A bolted-down, insulated cable is still a hazard in principle, but the risk is low. Risk assessment is the structured way of thinking this through before work starts, so that decisions about precautions are based on reasoning rather than habit or guesswork.
This article explains the logic in general terms. It is not a method for assessing a real task, and legal requirements for risk assessment differ between countries and sectors.
The basic steps
Many guides describe a similar sequence, with different names for the stages.
1. Identify the hazards
Start by looking at the work: the task, the place, the equipment, the materials, the people and the conditions. Walking the site, talking to the people who do the job, and reviewing past incidents and near misses all help. Workers who do a task every day often know hazards that managers miss.
Hazards can be physical (noise, heat, moving parts), chemical, electrical, ergonomic (awkward lifting, repetitive work), environmental (weather, uneven ground) or related to people and organization (fatigue, time pressure, lack of training).
2. Decide who might be harmed and how
Consider not just the person doing the task but also nearby workers, contractors, visitors and, at some sites, the public. Some people may be more vulnerable, such as new starters, those with certain health conditions, or workers unfamiliar with the site.
3. Judge the risk
For each hazard, ask two questions:
- Likelihood. How probable is it that the harm will happen, considering how often people are exposed and what controls already exist?
- Severity. If it did happen, how bad would the result be: minor first aid, serious injury, loss of life, damage to the environment, many people affected?
A common tool is a risk matrix, a grid with likelihood on one axis and severity on the other. Each combination is assigned a rating such as low, medium or high. The matrix helps compare risks and decide what needs attention first. It is a thinking aid, not a precise calculator, because the ratings rest on judgment. Two competent teams may rate the same task differently, which is why discussion and experience matter.
An important caution: a low-likelihood, extremely severe event can deserve more attention than its rating on a simple grid suggests, and estimates of rare events are uncertain by nature. That is one reason process safety specialists use more detailed methods for major hazards.
4. Decide on controls
Having judged the risk, the next question is what to do about it. The common approach is to follow the order of the hierarchy of controls: try to eliminate the hazard, then substitute something safer, then use engineering measures such as guards, then administrative measures such as procedures, signage and training, and finally protective equipment. Relying only on warnings and personal care is generally considered weaker than changing the situation itself.
After deciding on controls, the remaining risk, sometimes called residual risk, should be judged again. If it is still too high, more must be done, or the task should not go ahead.
5. Record and communicate
Findings are usually written down, at least for significant hazards, and shared with the people who do the work. A good record is brief and practical. A long document that nobody reads does little. Briefings before a job, sometimes called toolbox talks, help turn the assessment into shared understanding.
6. Review
Conditions change. Equipment is modified, weather shifts, new people join, and incidents reveal things that were missed. Assessments are normally reviewed after incidents, after changes, and at regular intervals. Feedback from workers is a key input. The insights from near miss reporting often show where an assessment was too optimistic.
A simple illustration
Imagine a technician needs to inspect equipment on an elevated platform. The hazard is a fall from height. Likelihood depends on factors such as edge protection, surface condition, weather and how long the person is exposed. Severity is high, because falls can cause serious injury. Following the logic above, the team asks whether the task can be done from the ground, whether permanent guardrails exist, whether safe access can be provided, and only then whether fall-arrest equipment and training are needed. The same logic applies to countless other tasks, though the actual decisions belong to trained, competent people on the site.
Different levels of assessment
Not every task needs a lengthy analysis. Typical workplaces use layers:
- General assessments of regular activities and areas.
- Task-specific assessments for particular jobs, often reviewed on the day by the team. Some organizations use a short “last minute risk assessment” prompt before starting.
- Detailed studies for high-hazard facilities, carried out by specialists, especially for design and major changes.
For high-risk tasks, an assessment often feeds into formal authorization such as a permit to work. Isolating energy sources, as described in the article on lockout tagout, is one common result of an assessment.
Key points
- A hazard is a source of potential harm; risk combines likelihood and severity.
- The main steps are identify, decide who is affected, judge risk, choose controls, record and review.
- Risk matrices support judgment but do not replace it, and rare severe events are hard to estimate.
- Controls are best chosen by removing or reducing the hazard, not only by asking people to be careful.
- Always follow the assessments and procedures that apply to your own workplace.