A job hazard analysis (JHA) — also called a job safety analysis (JSA) in some institutions — is a documented, step-by-step review of a specific lab procedure that identifies the hazard present at each step and the control assigned to it, before the procedure is performed for the first time or after it changes. It is the method most safety offices use to answer a narrower question than a full risk assessment: not “is this lab safe,” but “what can go wrong at each individual step of this one task, and what stops it.”
The JHA sits upstream of two other documents a lab already maintains. It feeds the standard operating procedure (SOP) — the JHA identifies the hazard and control, the SOP turns the control into an enforceable instruction — and it feeds the training record, because the JHA is what should be walked through with a new or transferring lab member before they run the procedure unsupervised.
When a JHA is needed
Not every lab task needs a written JHA. It is warranted for:
- Any new procedure being introduced to the lab, or an existing procedure moving to a new instrument, reagent, or organism.
- A procedure that has produced a near-miss, incident, or injury.
- A procedure involving a hazard class the lab tracks formally: chemical (especially reactive or pyrophoric compounds), biological, radiological, or physical (lasers, cryogens, high pressure, sharps, ergonomic strain).
- A procedure being performed by a new or infrequent user — a step order that is second nature to an experienced technician is exactly where a novice gets hurt.
Institutions vary on whether the JHA is required before every SOP is written or is triggered selectively by risk tier; check your institution’s environmental health and safety (EHS) office or institutional biosafety/chemical safety committee policy for which applies.
The four-step method
The structure below follows the four-step approach set out in OSHA’s Job Hazard Analysis guide (OSHA 3071), the reference most U.S. institutional EHS programs build their JHA templates from.
Step 1: Break the job into steps
Watch the procedure being performed, or walk through it in sequence if it is new, and break it into individual steps — typically 10 to 15 for a bench procedure of moderate complexity. Each step describes what is done, not how to do it well: “remove the sample vial from the liquid nitrogen dewar,” not “carefully remove the sample vial.” Too few steps (fewer than about 4) usually means a step is hiding more than one hazard; too many (more than about 20) usually means the task should be split into two JHAs.
Step 2: Identify the hazard at each step
For each step, ask what could realistically go wrong — not the worst theoretical case, but what happens if this step goes the way similar steps have gone wrong before. Work through the categories systematically rather than relying on memory for each step: struck-by or caught-in/between, chemical exposure (inhalation, skin, splash), biological exposure (sharps, aerosol, splash), electrical contact, thermal (cryogenic or heat), radiological, pressure/mechanical, and ergonomic (repetitive motion, awkward posture, manual handling). A single step commonly carries more than one hazard category.
Step 3: Determine the control for each hazard
For every hazard identified, assign a control using the hierarchy of controls, from most to least reliable:
- Elimination — remove the hazard from the procedure entirely (e.g., substitute a step that avoids an open flame near a flammable solvent).
- Substitution — replace the hazardous material or method with a less hazardous one (e.g., a less volatile solvent, a non-pyrophoric reagent where one is viable).
- Engineering controls — isolate people from the hazard through equipment or design (fume hood, biosafety cabinet, machine guarding, interlocks).
- Administrative controls — change the way people work (procedure sequencing, buddy system for high-risk steps, posted signage, restricted access during the step).
- Personal protective equipment (PPE) — the last line of control, not the first response, and only effective if selected for the specific hazard and actually worn correctly.
A JHA that lists PPE as the only control for most steps is a signal the analysis stopped too early — PPE should be layered on top of engineering and administrative controls, not substituted for them.
Step 4: List, rank, and record
Record the finished analysis in a table — step, hazard, control, and who is responsible for verifying the control is in place — and rank hazards by severity and likelihood so review time is spent first on the steps that carry the highest risk. This ranked table is what gets attached to the SOP and referenced in training sign-off, not a narrative summary.
Worked example: preparing a cryogenic sample for storage
The table below is an illustrative composite built to show the method, not a record of an actual institution’s JHA — treat it as a template to adapt, not a document to copy verbatim, since the correct controls depend on your specific instrument, cryogen volume, and room ventilation.
| Step | Hazard | Control(s) |
|---|---|---|
| 1. Transport liquid nitrogen dewar from storage to bench | Tip-over; cryogenic splash; confined-space oxygen displacement in transit (elevator) | Engineering: wheeled dewar cart with retention lip. Administrative: no-elevator-sharing policy for cryogen transport, or oxygen monitor if unavoidable. |
| 2. Open dewar and insert transfer wand | Cryo-burn from splash or contact; frostbite | PPE: cryogenic gloves and face shield. Administrative: slow, controlled insertion per SOP. |
| 3. Withdraw sample vial with tongs | Vial explosion from trapped liquid nitrogen (common with incompletely sealed cryovials) | Engineering: blast shield or face shield. Administrative: visual inspection of vial seal before storage; documented cool-down/venting step in SOP. |
| 4. Place vial in rack inside dewar | Cryo-burn from contact with cold rack or vapor | PPE: insulated gloves. Administrative: minimize hand time inside dewar neck. |
| 5. Log sample location and close dewar | Oxygen-depletion exposure if working in a poorly ventilated cold room over time | Engineering: room oxygen sensor with alarm. Administrative: limit unattended time in cold rooms; buddy system for extended work. |
For the underlying hazard mechanisms — oxygen displacement, cryo-burns, and dewar handling in more detail — see Liquid Nitrogen and Cryogen Handling.
Who signs off on a JHA
Sign-off practice varies by institution, but the roles are consistent: the person who performs the task (or the most experienced person performing it) drafts or reviews the step breakdown, since they know the actual sequence better than anyone writing from a manual; the principal investigator or lab manager approves the assigned controls and resourcing (e.g., agreeing to purchase an engineering control the analysis calls for); and EHS, the institutional biosafety committee, radiation safety office, or chemical safety committee reviews and signs off when the procedure falls under their jurisdiction (biological agents, radioactive material, Class 3B/4 lasers, particularly hazardous substances). The JHA should carry a review date and a defined trigger for re-review — a near-miss, an incident, a change in reagent, instrument, or personnel experience level, or a fixed interval (commonly annual) if nothing else has changed it sooner.
JHA vs. SOP vs. risk assessment: what each document is for
| Document | Question it answers | Scope |
|---|---|---|
| Job hazard analysis (JHA) | What is the hazard at each step of this specific task, and what controls it? | One task, step-by-step |
| Standard operating procedure (SOP) | What is the exact, enforceable sequence for performing this task? | One task, prescriptive instructions |
| Lab or protocol risk assessment | What is the overall risk profile of this lab, protocol, or biosafety/chemical hygiene program? | Whole lab, protocol, or program |
In practice, the JHA is the analysis step that produces the evidence base for the SOP’s safety-critical instructions (the control at each step) and for the broader risk assessment’s hazard inventory — it is not a substitute for either, and none of the three should be treated as satisfying the requirement for the others.
Frequently asked questions
How is a JHA different from a JSA?
They are the same method under two names — job hazard analysis (JHA) is the term OSHA’s guidance uses; job safety analysis (JSA) is used interchangeably by many institutions and industry safety programs. Check which term your institution’s EHS templates use so your documentation matches their filing system.
How many steps should a JHA have?
Most bench procedures break down into roughly 10 to 15 steps. Fewer than that usually means a step is bundling more than one hazard together; significantly more usually means the task should be split into two separate JHAs (for example, reagent preparation as one JHA and the instrument run as another).
Does a JHA replace a chemical hygiene plan or biosafety protocol?
No. A chemical hygiene plan and an institutional biosafety protocol are program-level documents covering broad categories of hazardous work; a JHA is task-specific and sits underneath them, documenting how that program’s general controls apply to one particular procedure’s individual steps.
Who is responsible for keeping the JHA up to date?
Typically the principal investigator or lab manager owns the document, but the trigger for revision should be explicit: a near-miss or incident involving the procedure, a change in reagent, equipment, or organism, or a fixed review interval if nothing else has prompted an update.
