Course 123 Introduction to Job Hazard Analysis

Writing Steps - Determining Hazards


The first step in preparing to conduct a JHA is to review all of the jobs in the workplace and make a list of those jobs that might require a JHA.

Involve Your Employees

Get together with your employees and talk about the actual and potential hazards and unsafe behaviors they believe might exist in their current work and surroundings. Discuss the possible accidents that might result from the hazards and behaviors. Next, come up with ideas to eliminate or control those hazards and behaviors. By the way, if you can eliminate or reduce hazards, don't wait until the JHA is conducted. Eliminate or reduce the hazard as soon as possible.

The JHA Format

In this course we use a very simple process and format for developing a JHA. The table below shows the basic layout of the form we'll be using. We'll fill in the columns later as we cover each topic. You will see a great variety of JHA forms used by various companies. As you can see below, the JHA format includes the job description and three columns:

  1. Basic Job Step
  2. Hazards - Possible Injuries
  3. Preventive Measures

JOB: _____________________________


Quiz Instructions

Each section in this course will include a quiz question at the bottom of the page. In the last section, you'll be able to check your score and retake the quiz if desired. Be sure to answer all questions or you won't see your score. To improve your score after you get results, just go back through the sections and change your answers. Do not refresh pages or you'll have to answer all questions again.

1. What is the first step in the JHA process?

a. Identify the hazards of each step
b. Develop the steps in the job
c. Review all jobs in need of a JHA
d. Receive approval from OSHA to conduct JHAs

Identify Hazards and Behaviors

Inherently hazardous!

During the job review process, focus on identifying hazardous conditions and unsafe behaviors. Remember, it takes a hazard and exposure to the hazard before an accident can occur. So, it makes sense to look for them during the review. Sources to help identify hazardous conditions and unsafe behaviors include Safety Data Sheets, Safety Committee reports, Maintenance reports, Safety Inspection and Accident Investigation reports, and existing work procedures.


If hazards that pose an immediate danger to an employee's life or health exist, take immediate action to protect the worker. Any problems that can be corrected easily should be corrected as soon as possible.


Some jobs may require potentially high-risk behaviors that should be identified in a JHA. High risk behaviors that might increase the probability and severity of an injury or illness include:

  • lifting, lowering, pushing, pulling and other manual handling operations
  • use of bridge cranes, man lifts, or other heavy equipment
  • working on or near energized equipment/components
  • operating vehicles (i.e. trucks, forklifts, etc.)
  • working within a confined space or under temperature extremes

2. During the job review process when conducting JHAs, focus on identifying _____.

a. hazards and conditions
b. hazardous conditions and unsafe behaviors
c. unsafe behaviors and poor attitudes
d. employees not using common sense

Conduct a Risk Analysis

Steps in a Risk Analysis
Click to enlarge.

Once you have identified jobs you believe might require a JHA, it's important to prioritize each job. To do this, analyze each job to determine their degree of risk. To determine the degree of risk objectively, it's important to know what risk is, so let's discuss the concept next.

Risk = Probability x Severity x Exposure

The overall risk inherent in a job is a function of three variables: probability, severity and exposure. The greater the probability, severity and exposure - the higher the risk while doing a job. More on this later.


Probability describes the likelihood that a worker will be injured or become ill if exposed to a hazard. Common terms used to describe probability are:

  • Unlikely - Injury from exposure has low probability. Less than 50% chance.
  • Likely - Injury from exposure has moderate probability. 50/50 chance.
  • Very Likely - Injury from exposure has high probability. Greater than 50% chance.
Severity is just a matter of luck.


Severity is an estimate of how serious the injury or illness will be as a result of an accident. The common terms used to describe severity are:

  • Minor - other than serious physical harm that does not prevent the employee from continuing to work in the same job.
  • Serious - serious physical harm that prevents the employee continuing to work in the same job.
  • Death - fatality
PPE would help protect this worker.


Exposure is the condition of being exposed to a hazard such that the employee is somehow affected by that hazard.

  • Physical exposure can be thought of as "arms length" exposure to physical hazards.
  • Environmental exposure occurs when the employee can suffer some kind of injury or illness as a result of a hazardous environment. Distance does not matter.

3. Which of the following is used to determine the risk of a job?

a. Common sense, severity, and history
b. Number of employees, severity, and best guess
c. History, likelihood, and anticipation
d. Probability, severity, and exposure
Risk Assessment Matrix
Click to Enlarge

The Risk Assessment Matrix

Another simple technique to help determine the overall risk of the jobs for which you'll be conducting a JHA, is called the Risk Assessment Matrix. It's a simple process to determine the risk level of each job:

  1. List all of the jobs that you are analyzing.
  2. Estimate the probability and severity of each job.
  3. Next, place the job in the appropriate section of the risk matrix.

Once you've entered all jobs, you can easily prioritize each job to determine which jobs to analyze first.

Prioritize Jobs - Worst First

Worst first!

Now that you have some idea how much risk is involved in each job, you can prioritize them. As mentioned earlier, a common strategy is to prioritize the most hazardous job first. If a JHA is required for many jobs in your workplace, priority should go to the following types of jobs, in order of priority:

  1. Jobs with the highest injury or illness rates;
  2. Jobs with the potential to cause injuries or illnesses, even if there is no history of previous accidents;
  3. Jobs in which one simple human error could lead to a severe accident or injury;
  4. Jobs that are new to your operation or have undergone changes in processes and procedures; and
  5. Jobs complex enough to require written instructions.

OSHAcademy Student Opinion: According to William I., it's important to understand that all the (potentially) "severe events" should be addressed first, then down to critical, etc. He has seen many cases where customers and safety professionals have focused on frequency issues because there is data to review and success to demonstrate. Meanwhile they ignore large loss potential events until they occur. In his opinion, as you address the large loss potential events, there is corollary benefit to the "less severe but more frequent" incidents.

4. Which of the following job categories would be considered the highest priority for a JHA?

a. Jobs that are new
b. Jobs that have undergone changes in processes
c. Jobs that could cause serious injury or illness
d. Jobs that have the highest injury or illness rates

Develop the Steps

List the steps in the job.

The process of "analysis" in the context of a JHA includes breaking the "whole" job down into its basic steps. The idea is to carefully describe actions and hazards within each step, and finally how to mitigate those hazards through preventive measures.

Every Step Has an Actor and Action(s)

Each step of a procedure describes what the worker (actor) does (action), so let's take a look at each of these two components:

  • Actor: The actor is the person accomplishing the action. The actor may perform or NOT perform a particular action in a step.
  • Action: An action is "the something" that is done by an actor. Actions may or may not be observable. Actions may describe an activity that is accomplished or not accomplished.
thinkstock photo 177377893
Each step has one actor and one or more actions.

If two or more employees are performing the job, identify the employee (actor) first and then the action(s). If only one employee is performing the job, there's no need to identify the actor.

Write the step in active tense. See the example of active and passive tense below:

  • Active tense: "Place the lockout device on the hasp."
  • Passive tense: "The lockout device is to be placed on the hasp."

The table below shows an example of the first three steps in the JHA. Notice that the two persons performing the job are identified.


1. Spotter: Spot position of trailer as it nears loading dock.
2. When the trailer is in position, turn engine off, set parking brake, and notify forklift operator.
3. Driver: Set chocks.

5. Every step in the JHA will include _____.

a. an environmental impact statement
b. a condition and event
c. an actor and an action
d. an object and subject

Describe the Hazards in Each Step

Look for possible hazards in each step.


A very important part in the JHA development process is to discover the hazards lurking within each step. A basic safety concept must be understood by all safety staff: to have an accident, a hazard and exposure to the hazard must exist.

  • A hazard is an unsafe condition that could cause injury or illness to an employee.
  • Exposure usually refers to an employee's placement relative to the hazard's "danger zone". If the employee is within the danger zone, the employee is exposed.

How To Identify Hazards

Whoah! Where's the guard?

A job hazard analysis is an exercise in detective work. Your goal is to discover the following:

  • What can go wrong?
  • What are the consequences?
  • How could the hazard arise?
  • What are other contributing factors?
  • How likely is it that the hazard will occur?

To make your JHA useful, document the answers to these questions in a consistent manner. Describing a hazard by answering the questions above ensures you target the most important contributors to the hazard. The hazard column in your JHA should identify the hazards, and the potential for exposure to hazards.

6. Each step in the JHA identifies _____.

a. many possible variations in outcomes
b. a hazard and exposure to the hazard
c. only one consequence per action
d. more than one actor or action

How To Identify Hazards (Continued)


Rarely is an accident a simple case of one single event or cause. More frequently, many contributing events tend to line up to cause hazardous conditions and unsafe behaviors. Here is an example of a hazard scenario that illustrates this idea:

Wood coming from the infeed rollers jammed up as it fell onto the chipper conveyor belt. A chipperman tried to clear the jam without turning off any part of the machine or using a picaroon. His hand and arm were caught up in the teeth of the rotating rollers, and his body was pulled onto the chipper conveyor. The chipperman's arm was twisted off at the shoulder. Another worker heard his cries and rescued him before he was pulled into the chipper. (Source: Worksafe BC)

Now, let's pretend the accident didn't happen and it was your job to identify the hazards and exposure inherent in this job. Let's ask the questions:

  • What can go wrong? The worker's hand could come into contact with a rotating object that "catches" it and pulls it into the machine.
  • What are the consequences? The worker could receive a severe or fatal injury.
  • How could it happen? The accident could happen as a result of the worker trying to clear a snag during operations or as part of a maintenance activity while the conveyor is operating. Obviously, this hazard scenario could not occur if the conveyor is not rotating.
  • What are other contributing factors? The hazards and exposure related to this job can occur very quickly. It does not give the worker much opportunity to recover or prevent it once his hand comes into contact with the rotating rollers. This is an important factor, because it helps you determine the severity and likelihood of an accident when selecting appropriate hazard controls. Unfortunately, experience has shown that training is not very effective in hazard control when triggering events happen quickly because humans can react only so quickly.
  • How likely is it that the hazard will occur? This determination requires some judgment. If there have been "near-misses" or actual cases, then the likelihood of a recurrence would be considered high. If the pulley is exposed and easily accessible, that also is a consideration. In this example, the likelihood that the hazard will occur is high because there is no guard preventing contact, and the operation is performed while the machine is running. By following the steps in this example, you can organize your hazard analysis activities.

7. What is TRUE about most accidents in the workplace?

a. Accidents are the result of isolated events
b. Many contributing events ultimately cause accidents
c. Accidents are usually caused by a lack of common sense
d. Accidents cannot be anticipated due to many variables

Common Hazards and Descriptions

Napo encounters many hazards.

Chemical (Flammable): A chemical that, when exposed to a heat ignition source, results in combustion. Typically, the lower a chemical's flash point and boiling point, the more flammable the chemical.

Chemical (Corrosive): A chemical that, when it comes into contact with skin, metal, or other materials, damages the materials. Acids and bases are examples of corrosives.

Explosion (Chemical Reaction): Self-explanatory.

Explosion (Over-Pressure): Sudden and violent release of a large amount of gas/energy due to a significant pressure difference, such as rupture in a boiler or compressed gas cylinder.

Electrical (Shock/Short Circuit): Contact with exposed conductors or a device that is incorrectly or inadvertently grounded. Example: a metal ladder comes into contact with power lines.

Electrical (Fire): Use of electrical power that results in electrical overheating or arcing to the point of combustion or ignition of flammables, or electrical component damage.

Electrical (Static/ESD): The moving or rubbing of wool, nylon, other synthetic fibers, and even flowing liquids can generate static electricity on the surface of material that can ignite flammables, damage electronics, or body's nervous system.

8. What kind of hazards can result in sudden and the violent release of a large amount of gas/energy?

a. Explosion (over-pressure)
b. Physical biohazards
c. Ergonomic hazards
d. Toxic substances

Common Hazards and Descriptions (Continued)

Workplace Ergonomics.

Electrical (Loss of Power): Safety-critical equipment failure as a result of loss of power.

Ergonomics (Strain): Damage of tissue due to overexertion (strains and sprains) or repetitive motion. Overexertion causes most workplace accidents.

Ergonomics (Human Error): A system design, procedure, or equipment that is error-provocative (A switch goes up to turn something off).

Excavation (Collapse): Soil collapse in a trench or excavation as a result of improper or inadequate shoring. Soil type is critical in determining the hazard likelihood.

Fall (Slip, Trip): Conditions that result in falls (impacts) from height or traditional walking surfaces (such as slippery floors, poor housekeeping, uneven walking surfaces, exposed ledges, etc.).

Fire/Heat: Temperatures that can cause burns to the skin or damage to other organs. Fires require a heat source, fuel, and oxygen.

Mechanical: Typically occurs when devices exceed designed capacity or are inadequately maintained. Skin, muscle, or body part exposed to crushing, caught-between, cutting, tearing, shearing items or equipment.

Noise: Noise levels (>85 dBA 8 hr TWA) that result in hearing damage or inability to communicate safety-critical information.

Radiation (Ionizing): Alpha, Beta, Gamma, neutral particles, and X-rays that cause injury (tissue damage) by ionization of cellular components.

Radiation (Non-Ionizing): Ultraviolet, visible light, infrared, and microwaves that cause injury to tissue by thermal or photochemical means.

9. Which hazard type causes more injuries in the workplace?

a. Mechanical hazards in general industry
b. Fall hazards on construction sites
c. Ergonomic hazards - overexertion
d. Chemical reactions - acid/basic burns

Common Hazards and Descriptions (Continued)

Struck By (Mass Acceleration): Accelerated mass that strikes the body causing injury or death (Examples are falling objects and projectiles).

Struck Against: Injury to a body part as a result of coming into contact of a surface in which action was initiated by the person. (An example is when a screwdriver slips.)

Temperature (Heat/Cold): Temperatures that result in heat stress, extreme exhaustion, or metabolic slow down such as hypothermia.

Toxin: A chemical that exposes a person by absorption through the skin, inhalation, or through the blood stream that causes illness, disease, or death.

Vibration: Segmental or whole-body vibration can cause damage to nerve endings, and organs.

Visibility: Lack of lighting or obstructed vision that results in an error or other hazard.

Weather Phenomena (Snow/Rain/Wind/Ice). Self-explanatory.

In the JHA form below, we have added some potential hazards and possible injuries that might occur as the worker performs each step in the form below.


1. Spotter: Spot position of trailer as it nears loading dock. Spotter could be caught between trailer and dock.
2. Driver: When trailer is in position, turn engine off, set parking brake, and notify forklift operator. Driver could be injured if he/she jumps off the truck.
3. Driver: Set chocks. Driver could strike head on trailer.
Driver could trip, slip, fall while in the dock well.

Identifying hazards in each step is a top priority to ensuring the overall effectiveness of the process of the JHA process. With that in mind, answer this last question, check your work, and head over to Module 2.

10. Materials that in small amounts may cause injury to skin and internal organs are considered _____.

a. toxins
b. radioactive
c. poisonous solids
d. chemical hazards

Check your Work

Click on the "Check Quiz Answers" button to grade your quiz and see your score. You will receive a message if you forgot to answer one of the questions. After clicking the button, the questions you missed will be listed below. You can correct any missed questions and recheck your answers.

Next Module


Watch this short video by Oregon OSHA that introduces you to what we'll be discussing in the next module: controlling hazards. They show a good example of how an engineering control can be the solution to a hazard.

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