4.3 Unsafe Acts vs Unsafe Conditions
Key Takeaways
- Unsafe acts are hazardous human behaviours—what people do or fail to do—that increase the chance of harm (for example shortcuts, removing guards, not wearing required PPE, working under the influence).
- Unsafe conditions are hazardous states of the workplace, equipment, or environment—what is wrong with the place or plant (for example unguarded machines, wet floors, poor lighting, damaged tools).
- Classic Heinrich-linked teaching attributes roughly 88% of accidents to unsafe acts and about 10% to unsafe conditions (with a small remainder often linked to other causes)—use these figures as examinable approximations.
- Both acts and conditions must be identified, reported, and corrected; focusing only on blaming workers while ignoring broken equipment is incomplete HSE practice.
- Clear examples and comparison tables help Level 1 candidates classify scenarios correctly under exam time pressure.
4.3 Unsafe Acts vs Unsafe Conditions
Hazard identification is not only about chemicals and machines. Many of the hazards you will meet—and many of the exam scenarios you will face—appear as unsafe acts or unsafe conditions. These two labels answer different questions:
- Unsafe act: What is the person doing (or not doing) that creates or increases danger?
- Unsafe condition: What is wrong with the workplace, equipment, or environment that creates or increases danger?
Getting this distinction right prepares you for accident-causation topics (including Heinrich’s domino model) and for practical reporting on Nigerian sites where supervisors ask: “Was it behaviour, condition, or both?”
Unsafe Acts: Human Behaviour
An unsafe act is a behaviour that deviates from safe practice and has the potential to cause harm. It is about people’s actions or omissions.
Common examples taught at Basic HSE level:
- Taking shortcuts to save time (bypassing a permit step, climbing instead of using the ladder provided)
- Not wearing required PPE (helmet, safety boots, eye protection, gloves, hearing protection)
- Removing or defeating guards and interlocks
- Using tools or equipment the person is not authorised or competent to use
- Horseplay, distraction with phones in line-of-fire areas, or unsafe positioning (standing under a load)
- Working under the influence of alcohol or drugs, or while unfit due to extreme fatigue against rules
- Failing to warn others or to isolate energy when required
- Ignoring exclusion zones, speed limits, or traffic rules on site
Unsafe acts are not always intentional malice. They may come from production pressure, poor training, habit, or a culture that rewards speed. Level 1 still classifies the behaviour as an unsafe act while later chapters deepen culture and system causes.
| Unsafe act | Why it is an act (not a condition) |
|---|---|
| Worker removes a machine guard to clean faster | Choice/behaviour of the person |
| Driver exceeds site speed limit | Behaviour while operating the vehicle |
| Technician works at height without required harness where mandated | Failure to follow required safe behaviour |
| Helper walks under a suspended load | Positioning behaviour in the line of fire |
| Employee reports for duty intoxicated | Behaviour / fitness-for-work failure |
Unsafe Conditions: State of the Workplace or Equipment
An unsafe condition is a physical or environmental state that has the potential to cause harm. It is about what is wrong with the place, plant, materials, or surroundings, independent of a single momentary behaviour (though behaviour may have created the condition earlier).
Common examples:
- Unguarded or inadequately guarded machinery
- Wet, oily, or uneven floors; blocked walkways; poor housekeeping
- Poor lighting in work or access areas
- Defective tools, frayed slings, damaged ladders, leaking hoses
- Missing handrails, open holes without covers or barriers
- Inadequate ventilation where fumes accumulate
- Exposed live electrical parts, damaged insulation
- Unstable stacking of materials
- Excessive noise or heat without corresponding workplace controls (the condition of the environment)
| Unsafe condition | Why it is a condition |
|---|---|
| Permanent floor opening with no cover or barrier | Workplace state |
| Burned-out lights in a stairwell | Environmental/workplace state |
| Pressure relief valve missing or known defective | Equipment state |
| Oil spill left across a walkway | Contaminated surface state |
| Scaffold with missing mid-rail | Structure/equipment state |
Comparison Table: Acts vs Conditions
| Feature | Unsafe act | Unsafe condition |
|---|---|---|
| Focus | Human behaviour | Workplace / equipment / environment state |
| Typical verb phrases | “did,” “failed to,” “bypassed,” “ignored” | “is missing,” “is damaged,” “is wet,” “is unguarded” |
| Primary control response | Coaching, competence, supervision, discipline where fair, procedures, culture | Repair, clean, guard, redesign, isolate, maintain, improve lighting/housekeeping |
| Who often first notices | Supervisors, co-workers, cameras, self-checks | Inspectors, workers walking the area, maintenance, audits |
| Can both exist together? | Yes—very often | Yes—very often |
Heinrich Link: The Classic Percentage Split
Basic HSE training commonly references Herbert W. Heinrich’s industrial accident research tradition. For Level 1 exam recall, remember the approximate split widely taught in introductory safety courses:
- About 88% of accidents are associated with unsafe acts
- About 10% are associated with unsafe conditions
- A small remainder (often taught as about 2%) is linked to unpreventable or other residual causes in the classic telling
Treat ~88% / ~10% as the examinable approximation used in many syllabi. Modern safety science discusses deeper system causes (management decisions, design, culture), and later chapters on Swiss cheese and safety culture expand that view. For this section’s exam questions, you still need the Heinrich-linked percentages and the act/condition vocabulary.
Important balance: Even if more accidents are historically linked to acts, fixing only workers while leaving broken guards and dark stairwells is bad practice. Conditions create the stage on which acts become catastrophic. Good HSE attacks both.
How Acts and Conditions Interact
Real incidents often chain together:
- Condition first: A walkway light fails (unsafe condition).
- Act next: A worker carries a load that blocks vision and hurries (unsafe act).
- Outcome: Trip and serious injury.
Or reversed:
- Act first: Someone leaves an oil drum uncapped after sampling (unsafe act).
- Condition created: Slippery pool and flammable vapour risk remains for the next shift (unsafe condition).
- Outcome: Another worker slips or a spark finds the vapour.
Exam scenarios may ask you to identify the unsafe act, the unsafe condition, or both. Read the stem for what is requested.
Scenario Practice Set
| Scenario | Classify | Notes |
|---|---|---|
| Electrician tapes over a safety interlock to keep a panel running | Unsafe act | Defeating a safety device is behaviour |
| Panel interlock is factory-broken and management left it in service | Unsafe condition (and management system failure) | Defective safety device left in place |
| Labourer refuses to wear provided safety boots in a nail-prone area | Unsafe act | PPE non-use is behaviour |
| Site never issued suitable boots and work proceeds anyway | Unsafe condition / system gap leading to exposure | Lack of suitable equipment is not “just the worker’s fault” |
| Crane wire rope shows broken strands still in use | Unsafe condition | Equipment state |
| Rigger knowingly uses the damaged rope to finish early | Unsafe act | Behavioural choice on defective gear |
| Heavy rain leaves clay mud on a ramp with no grit or barrier | Unsafe condition | Environmental/workplace state |
| Workers race down the muddy ramp despite warnings | Unsafe act | Behaviour on a known hazard |
How to Identify and Report Both
Identification habits
For unsafe acts (behaviour observation):
- Watch line-of-fire positions, PPE compliance, tool use, permit steps, and traffic rules
- Listen for “we always skip this step” language in toolbox talks
- Notice production pressure cues that push people toward shortcuts
For unsafe conditions (workplace inspection):
- Use structured walkabouts: access ways, emergency routes, guards, housekeeping, lighting, storage, leaks, signage
- Check tools and lifting gear before use
- Compare “as found” plant condition against what procedures assume
Reporting essentials (Level 1 practical standard)
- Make the area safe if you can do so without becoming a victim — for example, barrier an open hole if trained and equipped; do not enter a suspect confined space alone to “investigate.”
- Report promptly through the site method: supervisor, HSE officer, permit authority, hazard card, or digital report as required.
- Describe facts — what you saw, where, when, who may be exposed; avoid vague blame-only statements when a condition also exists.
- Separate act and condition in your wording when both apply: “Guard missing on conveyor (condition). Operator also reached toward the belt while running (act).”
- Follow up within your role — confirm temporary controls stay in place until permanent repair.
| Report ingredient | Example phrase |
|---|---|
| Location | “Pump house B, ground floor walkway” |
| Condition or act | “Oil leak across walkway” / “Workers crossing without clean-up request” |
| Immediate danger | “High slip potential for next shift” |
| Temporary control taken | “Area cordoned; absorbent requested” |
| Who notified | “Shift supervisor at 14:10” |
Why Reporting Culture Matters
If workers are punished for reporting near misses or minor unsafe acts made in good faith while learning, reporting dies and major accidents hide in silence. Level 1 supports a culture where:
- Deliberate reckless violations are addressed fairly and firmly
- Honest reporting of hazards and near misses is encouraged
- Conditions are fixed with the same energy used to coach behaviour
This dual approach aligns with professional HSE practice under ISPON-oriented training: people and plant both matter.
Exam Focus
- Define unsafe act as behaviour and unsafe condition as workplace/equipment state.
- Recall Heinrich-linked ~88% acts / ~10% conditions as the classic teaching split.
- Classify mixed scenarios carefully; select “both” when the stem supports it and that option exists.
- Prefer answers that require reporting and correction of both, not blame-only or condition-only thinking.
Which situation is the clearest example of an unsafe act?
According to the classic Heinrich-linked teaching used in many Basic HSE courses, approximately what share of accidents is associated with unsafe acts versus unsafe conditions?
A supervisor finds oil across a walkway (slippery surface) and also sees workers cutting through the area despite a temporary barrier tape that has been pushed aside. What is the best Level 1 classification?