Hazard, Error and Control: Agree What We Mean

Human Performance weekly series: lesson 1 of 52.

A 5–10 minute crew discussion, plus time to verify the actual controls. The crew talk and Word version are public. Separate supervisor and attendance records are included with free Safety & Systems membership.

Why this matters

When someone says the job is safe, what have they checked? Shared language helps a crew explain the exposure, the action that could go wrong, and the protection needed. Use one real task today. A useful explanation points to something the crew can verify, not just a reassuring word.

Learning objective

Describe one hazard, one possible error and one protective control, then identify evidence that the control meets its requirements.

Key hazards or failure points

Vague labels such as unsafe or careless; treating a reminder as physical protection; confusing a planned check with a completed check; assuming another person verified the control.

Practical controls

• Name the hazard: what could cause harm, who could be exposed, and during which step? Moving equipment, for example, creates a different exposure from a confusing instruction.
• Describe a possible error without judging the person: a missed handoff, wrong identifier or misunderstood signal. Ask what in the work could make that mistake easier.
• Name the control and its job. Explain how it removes the exposure, prevents contact or limits harm. Keep required safeguards in place; attention alone does not replace them.

Verify It in the Field

• At a safe briefing point, ask a worker to connect the three parts: hazard, possible error and protective control. Resolve different meanings before using the explanation in the JHA/JSA.
• Find the applicable procedure, manufacturer instruction, permit or other controlling source. Have the designated person identify the acceptance criterion and safe check method; do not create a limit in the discussion.
• For the selected control, review the actual finding, checker and time. Observe what can be confirmed safely and arrange any required specialist check. Record VERIFIED, HOLD or N/A with a reason. A planned inspection remains unverified.

Stop and reassess

Hold the affected step when the hazard or required protection is unclear, evidence is missing, or a control fails its criterion. Keep people out of exposure. Obtain the required correction and check, then use the site’s restart process. Calling something human error does not resolve the condition.

Crew discussion questions

• What can cause harm in our example, and to whom?
• What could make the intended action difficult or confusing?
• What evidence supports the control we are relying on?

For each required control, record its acceptance source and criterion, safe verification method, responsible checker, actual result and time. Use VERIFIED, HOLD/NOT VERIFIED, or N/A with a reason. A tick alone is not evidence. Complete all applicable task inspections; do not enter danger or improvise a test to fill out a form.

Leader preparation and practical detail

A delivery example that makes the words useful

Use an illustrative delivery route with hazardous movement prevented. The hazard is contact with moving equipment. A possible error is a pedestrian misunderstanding whether a crossing is open. The control might be the separation and crossing arrangement specified in the approved traffic plan. Ask the crew to explain how that arrangement protects someone who misunderstands the signal. Do not invent barrier ratings or separation distances. Compare the actual arrangement with the controlling plan and resolve gaps through the people authorized to approve it.

Replace a label with an observable condition

If someone says a worker was careless, ask what the person was trying to do and what information, equipment or help was available. Two similar identifiers or an interrupted handoff give the team something specific to improve. This conversation does not establish an incident’s cause. Capture the condition and arrange appropriate review. The useful result is a clearer task or stronger protection, with evidence that the change addresses the problem.

Keep the words connected to evidence

A control is planned when it appears in the job plan. It is installed when the specified arrangement is in place. It is verified when the required check has been completed against an applicable criterion. These are practical distinctions for this lesson, not regulatory definitions. A photo may show a barrier’s location without proving its capacity; a signature may identify the checker without describing the finding. Ask what the evidence establishes and what remains unresolved.

Short supervisor field check

• Task example identifies an actual exposure and affected people.
• Possible error is described as an action, with contributing work conditions.
• Control has a clear protective function and governing requirement.
• Designated verifier records criterion, safe method, finding and time.
• Unresolved protection is held; corrective owner and restart process are known.

Confirm the relevant trained/authorized people, unresolved items, interim protection, correction owner and recheck. Record required release authority and rebrief anyone affected. The separate sheet supports these records; it does not replace a specialist inspection, permit or engineering determination.

Attendance and follow-through

Use the separate attendance sheet for participants, roles, discussion concerns, actions and late-arrival rebriefs. Attendance is not proof of competence, functioning controls or authorization to work. Keep completed records private under employer procedures.

Source acknowledgment

This resource draws on the U.S. Department of Energy’s DOE-HDBK-1028-2009, Human Performance Improvement Handbook, Volume 2 (June 2009). Todd Jerome Jenkins makes no claim of authorship or copyright ownership in the original U.S. Government work. New explanations, examples, exercises and layouts are Todd Jerome Jenkins adaptations. No endorsement by DOE or the U.S. Government is implied. Third-party material credited in the handbook remains attributed to its source; this notice does not claim rights in that material.

Source excerpt: Volume 2/VOLUME 2 DEFINITIONS.pdf; Printed pp. 128, 129, 130. The June 2009 handbook supplies concepts; this lesson uses original explanations and exercises.

Technical scope and references

References reviewed October 9, 2026. DOE human-performance tools and OSHA recommended practices support preparation and discussion; they do not establish universal technical acceptance criteria. Apply the current task procedure, manufacturer instructions, permit and required competent or qualified decisions. A successful exercise does not replace required training, technical verification or work authorization.

1. DOE-HDBK-1028-2009, Volume 2 — Definitions — June 2009 guidance, printed pages 128–130: shared terminology, error precursors, defenses and verification. Applied exercise and plain-language definitions are original; nuclear-specific definitions and source wording are not reproduced.
2. NIOSH — Hierarchy of Controls — April 10, 2024 guidance: control selection and the value of protection less dependent on repeated human action.
3. OSHA — Hazard Prevention and Control — Recommended practices, action items 3 and 6: responsibility, implementation and evaluation of controls. Does not prescribe this toolbox form.

Connect this discussion to your JHA/JSA

Use the JHA/JSA planning and field-verification worksheet to record the actual task steps, hazards, responsible roles and controls. No task-specific worked example is linked for this topic yet. Return to What Changed Today? when the plan or conditions change.

Related Todd Jerome Jenkins articles: How to Conduct a Job Safety Analysis and What Is Human and Organizational Performance?.

Related crew discussions

• Pre Job Jha Jsa
• Human Performance Pre Job Check

Continue the weekly series

• Lesson 2: Task Preview: Prepare Before the Crew Briefing

Put one check into practice

Use the free JHA/JSA planning and field-verification worksheet to record today’s change, the required protection and the evidence needed before exposure.