Hazard analysis is the process of identifying potential sources of harm in a system, workplace, or process and evaluating which ones are serious enough to require controls. It’s used across industries, from food production to chemical manufacturing to healthcare, as the foundational step in preventing injuries, illnesses, and accidents before they happen.
OSHA considers the failure to identify or recognize hazards one of the “root causes” of workplace injuries and incidents. Hazard analysis exists to close that gap systematically rather than waiting for something to go wrong.
Hazard vs. Risk: A Key Distinction
These two terms are often used interchangeably, but they mean different things in safety work. A hazard is anything with the potential to cause harm. Risk takes that a step further by factoring in how likely that harm is to actually occur.
A useful way to think about it: two coastal areas might face hurricanes of equal destructive power, making the hazard identical. But if one area gets hit once every 20 years and the other once every 200 years, the first area faces ten times the risk. Risk is essentially the size of the hazard multiplied by the probability it will happen. Hazard analysis starts by cataloging what could go wrong, then feeds into risk assessment, which asks how likely and how severe each scenario really is.
Common Categories of Hazards
Hazards generally fall into a few broad categories, though the specific types you’ll encounter depend on your industry.
- Physical hazards: Things like explosions, fires, falling objects, extreme temperatures, radiation, or noise. In chemical settings, this includes flammable liquids and solids, oxidizers, materials that self-heat, gases under pressure, and substances corrosive to metal.
- Health hazards: Exposures that damage the body over time or immediately. These include toxic chemicals, carcinogens, skin and eye irritants, respiratory sensitizers, and substances that affect specific organs with single or repeated exposure.
- Biological hazards: Bacteria, viruses, mold, animal bites, or bloodborne pathogens. In food safety, biological contamination from pathogens like Salmonella or E. coli is a primary concern.
- Ergonomic hazards: Repetitive motions, awkward postures, heavy lifting, and poorly designed workstations that lead to musculoskeletal injuries over time.
The goal of categorization is simple: it gives teams a structured way to scan for hazards without overlooking entire classes of danger.
The Five Basic Steps
While specific methods vary, most hazard analyses follow a similar sequence:
- Identify the tasks or processes: Break the work down into specific steps or stages. In a factory, this might mean mapping each phase of a production line. On a job site, it means listing every physical task a worker performs.
- Identify hazards for each step: For every task, ask what could go wrong. Every possible source of energy, every chemical exposure, every point where human error could cause harm gets documented. OSHA emphasizes looking at the entire environment, not just the obvious dangers.
- Assess the risks: Determine the severity and likelihood of each hazard actually causing an incident. A hazard that could kill someone but occurs once in a million cycles is treated differently from one that causes minor burns every week.
- Develop controls: Create a list of actions to eliminate or minimize each risk. The most effective controls remove the hazard entirely. When that’s not possible, the focus shifts to engineering controls, procedural safeguards, and protective equipment.
- Document safe procedures: Write up step-by-step instructions that describe how to complete each task safely, incorporating all the controls identified above.
This isn’t a one-time exercise. Whenever a process changes, new equipment is introduced, or an incident occurs, the analysis needs to be revisited and updated.
How It Works in Food Safety (HACCP)
The most widely recognized application of hazard analysis in food is the HACCP system, which stands for Hazard Analysis and Critical Control Points. The FDA defines hazard analysis in this context as collecting and evaluating information on hazards associated with a food product to decide which ones are significant enough to include in a safety plan.
HACCP applies across the entire food chain, from growing and harvesting through processing, manufacturing, distribution, and preparation. Its seven principles have been adopted by government agencies, trade associations, and food companies worldwide. The first principle is conducting the hazard analysis itself: developing a list of hazards that are “reasonably likely to cause injury or illness if not effectively controlled.” From there, the system identifies critical control points (specific steps where controls can prevent or eliminate a hazard), sets limits, establishes monitoring, and defines corrective actions.
For a poultry processor, a critical control point might be the cooking step, where internal temperature must reach a specific threshold to kill harmful bacteria. The hazard analysis is what identified bacterial contamination as the significant danger and pointed to cooking as the place to control it.
Workplace Applications: Job Safety Analysis
In workplaces like construction sites, oil rigs, and manufacturing plants, hazard analysis often takes the form of a Job Safety Analysis (JSA). OSHA recommends this approach for any job that involves hazards or potential hazards, and especially for uncommon or rarely performed tasks where workers may be less familiar with the dangers.
A JSA breaks a job into a sequence of steps, identifies every conceivable hazard at each step, and then prescribes safe procedures to eliminate or control those hazards. Everyone involved in the task should be present when the JSA is written, because frontline workers often spot dangers that managers miss. The supervisor reviews, approves, and signs the JSA before work begins. If a job step changes at any point or a new step is introduced, the entire analysis gets reviewed and updated on the spot.
Specialized Methods for Complex Systems
Simple checklists work for straightforward jobs, but complex systems like chemical plants, aircraft, and hospitals require more structured approaches. Several formal methods have been developed, each with strengths suited to different situations.
A HAZOP study (Hazard and Operability) is one of the most established approaches in process industries like oil refining and chemical manufacturing. A multidisciplinary team systematically works through a process design, brainstorming what happens when conditions deviate from normal. What if the temperature is too high? What if flow stops? What if pressure exceeds design limits? Each deviation is examined for its causes, consequences, and safeguards.
FMEA (Failure Mode and Effects Analysis) takes a different angle. Instead of looking at process deviations, it asks how individual components or steps could fail and what the downstream effects would be. It’s one of the most widely used risk assessment methods across manufacturing, aerospace, automotive, and electronics industries. Teams assign severity, occurrence, and detection scores to each potential failure to prioritize which ones need attention first.
Fault Tree Analysis works backward from an undesired event, mapping out all the combinations of failures that could lead to it. It’s been used in aviation safety for decades.
These methods overlap significantly in their ability to identify and reduce risks, and organizations often use more than one. A chemical plant might use HAZOP during the design phase and FMEA for ongoing equipment maintenance.
Hazard Analysis in Healthcare
Hospitals and clinical settings have adapted these industrial tools for patient safety. The VA healthcare system developed Healthcare Failure Mode and Effect Analysis (HFMEA) specifically for medical environments. It streamlines the traditional FMEA process by combining several evaluation steps into a simplified decision tree, making it more practical for clinical teams who need to assess risks in medication administration, surgical procedures, or diagnostic processes.
Rather than calculating complex numerical scores, HFMEA uses a hazard matrix that lets teams read a hazard score directly, speeding up the analysis without sacrificing rigor. This matters in healthcare, where the “components” that can fail include human judgment, communication between providers, and handoffs between departments.