A job safety analysis (JSA), also called a job hazard analysis, breaks a job into its individual steps, identifies what could hurt someone at each step, and assigns a specific control for every hazard. It is done before the work starts, on a one-page worksheet the crew can actually use.
Done right, a JSA is the most practical safety document in the plant: it turns "be careful" into a named hazard and a named control at the exact step where someone gets hurt. Done wrong, it is a form filled out at a desk to satisfy an audit. The difference is specificity and who holds the pen. This post covers both, using OSHA's own guidance as the reference; it is educational, not legal advice.
Is a JSA the same as a JHA?
Yes. Same tool, two names. OSHA's guide, Job Hazard Analysis, Publication 3071 uses "job hazard analysis"; much of industry says "job safety analysis," and some plants say JSEA or task hazard analysis. OSHA 3071 defines the technique as one that focuses on job tasks as a way to identify hazards before they occur, centered on the relationship between the worker, the task, the tools, and the work environment. Whatever your plant calls it, the mechanics are identical: steps, hazards, controls.
What goes on a JSA worksheet?
Three columns and a header. The header identifies the job, the date, who did the analysis, who reviewed it, and the PPE and tools the job requires. The body is a table: the job's steps in order, the hazards present at each step, and the control assigned to each hazard. One page. If it runs to three pages, the job was broken down too fine or the job is really several jobs.
A blank, printable version of this worksheet is attached to this post as a downloadable template.
Which jobs should you analyze first?
Start where the injuries are. You cannot JSA every job at once, and OSHA 3071's priority logic is the right order:
- Jobs with the highest injury or illness rates in your own history.
- Jobs with near misses the injuries that have not happened yet.
- Jobs where one human error could cause a severe injury, even with a clean history.
- Jobs that are new to the operation, or that changed in process or equipment.
- Jobs complex enough to need written instructions, and jobs performed rarely enough that nobody remembers them well.
A rarely performed, complex job is the sleeper on that list. The annual gearbox swap has no injury history because it happens once a year, and it happens once a year with a crew that has half-forgotten it. That is exactly the job that deserves a worksheet.
How do you write a JSA? The five-step process
- Select the job using the priority logic above, and tell the crew why. A JSA announced as fault-finding gets sandbagged; one announced as "we want this job to stop biting people" gets help.
- Break the job into steps ideally by watching it done by the person who normally does it. Aim for 6 to 10 steps. Too granular and nobody reads it; too coarse and hazards hide inside a step like "remove the old die."
- Identify the hazards at each step and write them specifically: "crushed by unsupported die during change," not "pinch point." A hazard that names the mechanism of injury points at its own control. One that says "caught in machine" points at nothing.
- Assign a control to every hazard taking the highest feasible option on the hierarchy of controls rather than defaulting to PPE. Every hazard on the sheet gets a control; a blank cell means the analysis is not finished.
- Review, approve, train, and revisit. The supervisor and the operator both sign it, the crew is trained on it, and it gets re-opened after any incident, near miss, or change to the job.
How do you pick the right control for each hazard?
Work down NIOSH's hierarchy of controls: elimination, then substitution, then engineering controls, then administrative controls, then PPE, in descending order of effectiveness. The top of the hierarchy removes the hazard; the bottom asks a human to behave perfectly near it, every time.
Run the die-change hazard through it. "Crushed by unsupported die during change" could be controlled by a die cart that keeps hands out from under the load entirely (elimination of the exposure), a support block or interlock (engineering), a two-person procedure (administrative), or gloves and steel toes (PPE, and nearly useless against a falling die). The worksheet should record the highest of those that is feasible, not the cheapest to write down. And when a step involves servicing a machine, the control is usually energy isolation: the JSA should name the machine's specific lockout/tagout procedure, not just note "LOTO required."
Who should write the JSA?
The person who does the job, together with a supervisor or safety lead. The operator knows the real sequence, the shortcuts, and the step where the wrench always slips; a JSA written alone at a desk describes the job as imagined, not as performed. Watching the job done is also the fastest way to surface the workarounds nobody documented, and pairing the analysis with the operator makes the training in step 5 nearly free, because the crew helped write the thing they are being trained on.
How do you keep a JSA from going stale?
Re-open it on a trigger, not on a shelf schedule alone: after every incident or near miss involving the job, after any change to the equipment, materials, or process, and on a fixed review cycle for the highest-risk jobs. Use it as onboarding material for new hires, and pull single rows from it as ready-made toolbox talk topics. A periodic safety audit should sample JSAs against the job as actually performed; the gap between the sheet and the floor is the measure of whether your program is alive.
What do the numbers say?
The scale of what JSAs are trying to prevent, from the primary sources:
- Private industry employers reported 2.6 million nonfatal workplace injuries and illnesses in 2023 per the Bureau of Labor Statistics.
- BLS counted 5,283 fatal work injuries in 2023 and 5,070 in 2024.
- OSHA's Job Hazard Analysis guide (Publication 3071) is free, short, and includes worked examples and a sample form.
Behind each of those numbers is a job step that went differently than someone expected. That is precisely the unit a JSA works on: not the plant, not the shift, the step.
One last practical point: in most plants, JSA worksheets live on paper, in a binder near the supervisor's desk, which means they are invisible at the moment of work and unsearchable after it. Harmony is an AI-native layer that connects machines, software, and paperwork into one operational layer, with no rip-and-replace: paper forms and checklists become structured data captured on tablets at the station, searchable and auditable, the everyday shape of connected worker technology. AI search returns cited answers across SOPs, logs, and quality records, so the JSA for a job surfaces when someone searches the job instead of staying filed under a title nobody remembers. Harmony's digital workflows move paper logs, forms, and handoffs into that structure; it is not a safety-compliance product, but it keeps the worksheet where the work is.