Physical Hazards in the Health Workers’ Environment

Physical Hazards in the Health Workers’ Environment

By the end of this lesson, the learner should be able to:

• Define a physical hazard, exposure, dose, injury and occupational disease.
• Identify physical hazards in emergency, pre-hospital, inpatient, theatre, laboratory, radiology and support environments.
• Explain the sources, health effects and prevention of heat, cold, lighting, noise and vibration hazards.
• Distinguish ultraviolet, ionising and non-ionising radiation and describe appropriate controls.
• Recognise electrical, pressure, fire, slip, trip, fall and vehicle hazards in health care.
• Explain how exposure intensity, duration, frequency, distance, susceptibility and combined hazards influence risk.
• Carry out a physical-hazard risk assessment and apply the hierarchy of controls.
• Apply safe practices for emergency procedures, ambulance operations, oxygen cylinders, equipment and patient movement.
• Describe immediate first aid and reporting after common physical injuries.
• Use scenarios and examination questions to prioritise safe action in an emergency-medicine workplace.

1. Definitions and core concepts

2. Sources of physical hazards in health care

3. How physical exposure causes harm

• Transfer of energy: electricity, radiation, heat, pressure and moving machinery transfer energy to the body and damage tissue.
• Environmental strain: heat, cold, noise, vibration and poor lighting stress body systems or reduce performance.
• Mechanical impact: falls, collision, crush, cuts and uncontrolled equipment cause immediate injury.
• Reduced attention: glare, noise, fatigue, heat and vibration impair communication, concentration and decision-making.
• Cumulative dose: repeated low-level exposure can eventually cause disease even when no single shift feels dangerous.
• Combined hazards: a wet floor plus poor lighting, or a noisy ambulance plus fatigue, creates more risk than either hazard alone.

4. Heat hazards

4.1 Definition and sources

Heat stress occurs when the body gains or produces more heat than it can lose. Health workers may encounter hot ambulance compartments, crowded emergency rooms, kitchens, boiler or laundry areas, outdoor scenes, protective clothing, direct sunlight, fires, hot water, steam and poorly ventilated rooms. PPE can reduce heat loss and increase sweating, so a worker may become overheated even when the surrounding temperature is moderate.

4.2 Heat-related effects

• Heat rash: itchy irritated skin caused by blocked sweat ducts.
• Heat cramps: painful muscle spasms after sweating and loss of water and electrolytes.
• Heat syncope: faintness or collapse related to heat, dehydration and pooling of blood.
• Heat exhaustion: weakness, headache, dizziness, nausea, heavy sweating, thirst, irritability and reduced performance.
• Heat stroke: a life-threatening emergency with altered mental state and severe overheating; sweating may be present or absent. It requires rapid cooling and urgent medical care.
• Dehydration: reduced circulating volume, dark urine, dry mouth, tachycardia, fatigue and impaired concentration.
• Medication and disease effects: diuretics, anticholinergics, cardiovascular disease, fever, pregnancy and obesity may reduce heat tolerance.

4.3 Prevention and control of heat

• Provide ventilation, shade, fans or air conditioning where feasible and safe.
• Schedule heavy tasks during cooler periods and rotate staff when exposure is prolonged.
• Allow rest and hydration according to the risk assessment and local policy.
• Use breathable clothing where it does not compromise infection control; plan work-rest cycles for impermeable PPE.
• Train workers to recognise early symptoms and use a buddy system during major incidents.
• Never leave a patient, oxygen cylinder or worker in a hot, closed vehicle without monitoring and a safe plan.

5. Cold hazards

Cold stress occurs when the body loses heat faster than it can produce it. Health workers may face cold rooms, refrigerated storage, cold rain, night response, wet clothing, air-conditioned theatres, cold ambulance compartments or prolonged contact with cold water. Cold also reduces finger dexterity and judgement, which can cause errors during emergency procedures.

• Provide dry, insulating clothing and waterproof outer layers.
• Change wet clothing promptly and protect hands, feet, head and face.
• Use warm rest areas and schedule breaks during prolonged cold exposure.
• Maintain safe ambulance heating and ventilation without creating a fire or carbon-monoxide risk.
• Warm a hypothermic person gradually according to clinical protocol; handle gently and monitor continuously.
• Do not rub frostbitten tissue, apply direct dry heat or allow the person to walk on severely affected feet.

6. Lighting hazards

Lighting becomes a physical hazard when it is insufficient, excessive, uneven, flickering, poorly directed or produces glare. A clinician may see enough to work but still miss a colour change, monitor alarm, wet patch, sharps injury or medication label.

7. Noise hazards

Noise is excessive, unwanted or harmful sound. It may be continuous, intermittent or impulsive. In emergency medicine, sirens, alarms, suction, oxygen flow, generators, compressors, patient distress, loud conversations and construction can combine. Noise may damage hearing, but it can also hide warnings and compromise patient safety.

• Control noise at the source through equipment maintenance, quieter devices and isolation of generators or compressors.
• Separate noisy functions from clinical communication areas and close doors where safe.
• Reduce unnecessary alarms while preserving clinically important alerts.
• Use clear visual signals and closed-loop communication when noise cannot be avoided.
• Limit time in high-noise areas and provide hearing protection where the risk assessment requires it.
• Arrange hearing conservation and medical review for persistent tinnitus or hearing difficulty.

8. Vibration hazards

Vibration is oscillating motion transmitted from a tool, machine, vehicle or surface to the body. The two major forms are hand–arm vibration and whole-body vibration.

Vibration may combine with cold, awkward posture, heavy lifting and long driving. A driver who is tired, numb and unable to feel the pedals or steering wheel is a safety risk even if the vibration alone seems tolerable.

9. Ultraviolet and non-ionising radiation

Ultraviolet (UV) radiation is invisible electromagnetic energy from sunlight, welding arcs, germicidal lamps and specialised equipment. Other non-ionising sources include visible intense light, infrared energy, radiofrequency and some lasers. The effect depends on wavelength, power, distance, exposure time and whether the eyes or skin are protected.

10. Ionising radiation

Ionising radiation has enough energy to remove electrons from atoms and molecules. In health care it may come from X-ray equipment, CT, fluoroscopy, radiotherapy, nuclear medicine and radioactive materials. Ionising radiation can damage cells directly or through free radicals; the risk depends on dose, tissue sensitivity and cumulative exposure.

10.1 Health effects

• Deterministic/tissue effects: occur above a threshold and become more severe as dose increases, such as skin injury, cataract or tissue damage.
• Stochastic effects: the probability of long-term effects, including cancer, increases with cumulative exposure; severity is not predicted by dose in the same way.
• Reproductive and fetal concerns: pregnancy must be managed through confidential risk assessment and radiation-safety procedures, not stigma or automatic exclusion.
• Acute high exposure: can cause systemic illness and requires specialised emergency management.

10.2 Radiation protection principles

11. Electrical hazards

Electricity can cause shock, burns, muscle tetany, arrhythmia, respiratory arrest, falls and fire. In health care the risk increases when electricity is combined with wet floors, oxygen-enriched environments, damaged cables, overloaded sockets, poor grounding or untrained repairs.

11.1 First action at an electrical incident

1. Do not touch the casualty while they remain connected to the source.
2. Switch off or isolate the power using a safe method; call for trained help.
3. Once the source is isolated, assess airway, breathing and circulation and begin emergency care.
4. Look for entry and exit burns, falls, fractures and internal injury; electrical injury may be more serious than the skin appears.
5. Arrange urgent clinical assessment and report the incident.

12. Pressure, compressed gases and stored energy

Compressed oxygen, air, nitrous oxide and other gases store energy. Cylinders can become dangerous projectiles if they fall or the valve breaks. Pressure vessels, autoclaves and suction systems can rupture or cause sudden release of energy when poorly maintained or opened incorrectly.

• Secure cylinders upright with approved chains or holders; do not leave them loose on a trolley or ambulance floor.
• Keep valves, regulators and connectors clean and compatible; never use oil or grease on oxygen equipment.
• Open valves slowly and stand to the side where appropriate; do not modify regulators.
• Separate full and empty cylinders, label them clearly and keep them away from heat and ignition sources.
• Inspect hoses, pressure gauges and safety valves and remove defective equipment from service.
• Do not open an autoclave or pressure vessel until the cycle is complete and the pressure has safely returned to normal.
• Train staff in cylinder transport, storage, fire response and emergency shut-off procedures.

13. Slips, trips, falls and unsafe surfaces

After a fall, do not rush to lift the person. Assess for head, neck, spinal, hip and limb injury, call for assistance, preserve the scene where necessary and document the event.

14. Fire, smoke and explosion hazards

Hospitals contain oxygen, electrical equipment, flammable products, cooking areas, generators, batteries and combustible linen. An emergency worker must know the facility fire plan, alarm route, evacuation points, extinguisher locations and the limits of their training.

• Keep exits, fire doors and corridors clear; never wedge fire doors open unless the facility plan permits it.
• Store oxygen and flammable materials correctly and separate ignition sources.
• Report overheating equipment, burning smells, sparks and damaged plugs immediately.
• Know the facility’s alarm and evacuation procedure, including support for patients who cannot walk.
• Use only an extinguisher you are trained and authorised to use; do not fight a growing fire alone.
• In an oxygen-fed fire, close the oxygen source only if it is safe and within the emergency procedure.
• Smoke inhalation may cause serious injury even without external burns; assess airway and arrange urgent care.

15. Ambulance, vehicle and roadside physical hazards

16. Manual handling and patient movement

Although ergonomics is taught separately, patient handling also creates an immediate physical injury risk. Heavy or uncooperative patients, limited space, slippery floors, uneven ground and emergency urgency can produce back, shoulder, neck and limb injuries.

• Assess the weight, condition, cooperation, route, obstacles and equipment before lifting.
• Use a mechanical aid, stretcher, slide sheet or additional trained personnel where available.
• Explain the movement and coordinate with a clear leader and commands.
• Keep the load close, avoid twisting and use stable footing.
• Do not attempt a heroic lift that places the whole team at risk; request help.
• After a worker injury, stop and report rather than normalising pain as part of the job.

17. Risk assessment for physical hazards

18. Hierarchy of controls

19. Controls by physical hazard

20. Health surveillance and reporting

• Baseline assessment helps identify pre-existing hearing, vision, musculoskeletal, skin or respiratory problems.
• Hearing checks are important when work includes repeated high noise.
• Vision assessment supports workers exposed to intense light, screens, precision tasks or radiation work.
• Radiation workers should follow the facility dosimetry and medical-surveillance programme.
• Repeated back pain, numbness, tinnitus, eye symptoms, heat illness or cold injury should be reported early.
• Near misses, equipment defects, falls, burns, shocks and vehicle incidents must be recorded and investigated.
• Reporting should improve systems rather than punish a worker who raises a genuine safety concern.
• Managers should review patterns by shift, location, equipment, task and worker group and then implement corrective action.

21. Immediate response to common physical injuries

22. Uganda health-facility and legal context

Uganda’s Occupational Safety and Health Act, 2006 requires employers and occupiers to provide safe premises, safe access and exit, suitable lighting, sanitary and washing facilities, safe working conditions, information, training, supervision and protective equipment. It also addresses dangerous substances, machinery, lifting equipment, first aid and workplace records. In health care, these duties translate into functional emergency equipment, safe electrical installations, maintained ambulances, radiation protection, safe oxygen storage, clear evacuation routes, adequate lighting, housekeeping and a system for reporting defects and injuries.

23. Emergency-medicine scenarios

24. Common mistakes

• Calling a hazard “safe” merely because no one has yet been injured.
• Using a lead apron, gloves or safety shoes while leaving the source hazard uncontrolled.
• Standing close to an X-ray beam because the exposure will be “only one image.”
• Ignoring a damaged cable, loose cylinder, broken wheel or flickering lamp.
• Mopping a busy corridor without warning signs or an alternative route.
• Walking through a wet area while carrying a patient or emergency equipment.
• Continuing to drive while dehydrated, dizzy, fatigued or numb from vibration or cold.
• Using a chair as a ladder or reaching from an unstable trolley.
• Confusing a surgical mask with hearing, radiation or respiratory protection for a different hazard.
• Rubbing frostbitten skin or applying direct high heat to a cold injury.
• Touching an electrically injured person before isolating the source.
• Overlooking the physical hazards faced by cleaners, porters, drivers, laundry workers and students.
• Failing to investigate near misses and repeated equipment defects.

25. High-yield comparisons

26. Revision questions

1. Define a physical hazard and distinguish it from physical risk.
2. List eight physical hazards found in a health-worker environment.
3. Explain how intensity, duration and frequency affect exposure.
4. Describe four sources of occupational heat in emergency medicine.
5. Differentiate heat exhaustion from heat stroke.
6. List six signs of cold stress or hypothermia.
7. What controls reduce lighting-related errors?
8. Explain how noise can cause both hearing injury and clinical errors.
9. Differentiate hand–arm from whole-body vibration.
10. List the health effects of prolonged vibration.
11. What are the sources and effects of ultraviolet radiation?
12. Differentiate ionising from non-ionising radiation.
13. Explain time, distance, shielding and ALARA in radiation safety.
14. Why can electrical hazards be more dangerous around oxygen and water?
15. State the correct first action when a worker is attached to an electrical source.
16. List five precautions for compressed oxygen cylinders.
17. Identify causes of slips, trips and falls in a hospital.
18. What should be done before lifting a patient from the floor?
19. Explain the hierarchy of controls using a wet-floor example.
20. What checks should be completed before an ambulance departs?
21. Describe the immediate response to a suspected heat stroke.
22. Why should frostbitten tissue not be rubbed?
23. What information should be recorded after a physical injury or near miss?
24. How does poor lighting affect emergency procedures?
25. Using one scenario, show how an EMT protects self, partner, patient and bystanders from physical hazards.

27. Final physical-safety checklist

• Scan the scene for heat, cold, noise, lighting, electricity, radiation, traffic, pressure and unstable surfaces.
• Control the source before relying on PPE.
• Keep floors, exits, cables, cylinders and equipment organised.
• Use time, distance and shielding whenever radiation is present.
• Secure the patient, team and equipment before vehicle movement or patient transfer.
• Never touch an electrical casualty before the power is isolated.
• Report defects, falls, burns, shocks, near misses and symptoms early.
• Protect cleaners, drivers, porters, students and support staff as carefully as clinical staff.
• Use safe systems every shift, not only after someone is injured.

Further reading and source notes

• Supplied SlideShare: Occupational Hazards — Physical Hazards.
• International Labour Organization: Physical Hazards and Risks.
• WHO: Occupational Hazards in the Health Sector.
• WHO: Protecting the Health and Safety of Health Workers.
• CDC/NIOSH: Work-Related Risks and Hazards in Health Care.
• CDC/NIOSH: Hierarchy of Controls.
• Uganda: Occupational Safety and Health Act, 2006.