LO2: Risks to Health and Safety
Unit 1: Safety and Security in Construction
AC2.1 — Hazards on a Construction Site
A hazard is anything that has the potential to cause harm. Construction sites are full of hazards because of the nature of the work — heavy materials, powerful machinery, working at height, and many different trades working in the same space.
Hazards can be grouped into categories:
Physical Hazards
Physical hazards are the most common type on a construction site.
| Hazard | Example |
|---|---|
| Working at height | Scaffolding, roofwork, ladders, open floor edges |
| Moving plant and vehicles | Excavators, dumper trucks, forklift trucks |
| Manual handling | Lifting bricks, blocks, timber, pipes |
| Hand-arm vibration (HAV) | Using drills, disc cutters, compactors |
| Whole-body vibration | Operating plant on rough ground |
| Noise | Power tools, compressors, pile driving |
| Falling objects | Materials or tools dropped from height |
| Excavations and trenches | Risk of collapse or falling in |
| Electricity | Overhead power lines, buried cables, site wiring |
| Structural instability | Partially demolished or newly erected structures |
| Slips, trips and falls | Uneven ground, mud, wet surfaces, trailing cables |
| Confined spaces | Manholes, drainage trenches, tanks |
Chemical Hazards
| Hazard | Example |
|---|---|
| Silica dust | Cutting, grinding or drilling concrete, stone or brick |
| Cement and lime | Skin and eye contact — can cause burns and dermatitis |
| Asbestos | Found in older buildings being refurbished or demolished |
| Solvents | Adhesives, paints, varnishes — inhalation or skin contact |
| Carbon monoxide | Petrol/diesel engines running in enclosed spaces |
| Lead | Old paintwork in refurbishment projects |
Biological Hazards
| Hazard | Example |
|---|---|
| Leptospirosis (Weil’s disease) | Contact with water or soil contaminated by rat urine |
| Tetanus | Cuts and wounds exposed to contaminated soil |
| Legionella | Water systems in buildings being refurbished |
Ergonomic Hazards
These relate to the way work is carried out and how it affects the body over time.
- Repetitive movements (e.g. using a trowel)
- Awkward postures (e.g. working in confined spaces or overhead)
- Poorly designed tools or workstations
Psychosocial Hazards
- Work-related stress from tight deadlines, long hours, or poor management
- Bullying and harassment on site
AC2.2 — Risks Associated with Hazards
A risk is the likelihood that a hazard will actually cause harm, combined with the severity of that harm. The same hazard can present different levels of risk depending on the situation.
Hazard = the source of danger Risk = the chance that harm will result
Risks from Working at Height
Working at height is the single biggest cause of fatal and major injuries in construction. Risks include:
- Falls from scaffolding — can cause fatal head injuries, spinal injuries, multiple fractures
- Falls through fragile roofs — skylights and roof lights are a common cause of falls
- Falls from ladders — often due to overreaching or using a ladder in poor condition
- Falling objects — tools or materials dropped from height can kill workers below
Risks from Moving Plant and Vehicles
Construction vehicles are involved in a significant number of fatalities each year:
- Workers being struck by reversing vehicles — particularly dumper trucks and excavators
- Workers being run over — poor visibility from cab, no banksman present
- Overturning of plant on unstable ground
- Collisions between plant and other site traffic
Risks from Manual Handling
Manual handling injuries account for over a third of all workplace injuries:
- Back injuries — sprains and strains, prolapsed discs
- Upper limb disorders — shoulder, arm and wrist injuries
- Crush injuries — materials slipping or falling while being carried
Risks from Hand-Arm Vibration
Prolonged use of vibrating tools can cause Hand-Arm Vibration Syndrome (HAVS):
- Vibration White Finger (VWF) — reduced blood flow causes fingers to turn white and numb in cold conditions
- Permanent damage to nerves and blood vessels — the condition is irreversible once it develops
Risks from Noise
Exposure to high levels of noise causes noise-induced hearing loss (NIHL):
- Gradual and permanent — workers often don’t notice until significant damage is done
- Tinnitus (ringing in the ears)
- The Control of Noise at Work Regulations 2005 sets action levels:
- 80 dB(A) — employer must provide information and make hearing protection available
- 85 dB(A) — employer must provide hearing protection and ensure it is worn
Risks from Hazardous Substances
| Substance | Associated Disease / Condition |
|---|---|
| Silica dust | Silicosis (irreversible lung scarring), lung cancer |
| Asbestos | Mesothelioma, asbestosis, lung cancer — often fatal |
| Cement | Contact dermatitis, chemical burns |
| Solvents | Dermatitis, headaches, damage to liver/kidneys with long-term exposure |
Risks from Excavations
- Collapse of trench sides — can bury workers, causing fatal crush injuries or asphyxiation
- Flooding — from surface water or underground water
- Striking buried services — gas, water, electricity and telecommunications cables
Risks from Electricity
- Electrocution — striking buried cables during excavation or drilling; contact with overhead lines
- Arc flash — intense heat and light from electrical arc
- Fire — faulty wiring or overloaded circuits
AC2.3 — Risk Assessments
A risk assessment is a systematic examination of work activities to identify hazards, evaluate the likelihood and severity of harm, and decide on appropriate control measures.
Under the Management of Health and Safety at Work Regulations 1999, employers with five or more employees must carry out and record risk assessments.
The Five Steps of Risk Assessment
Step 1 — Identify the hazards
- Walk around the site and look at what could cause harm
- Consult workers — they often know about hazards the manager hasn’t noticed
- Check accident books and near miss reports
- Consult manufacturers’ data sheets for hazardous substances
Step 2 — Decide who might be harmed and how
- Consider all groups: site workers, subcontractors, visitors, members of the public
- Think about people with particular vulnerabilities — new workers, young workers, those with disabilities, pregnant workers
Step 3 — Evaluate the risks and decide on precautions
- Consider how likely it is that harm will occur and how serious that harm would be
- Use the hierarchy of control (see below) to decide what controls are needed
- Consider what is already in place and whether more needs to be done
Step 4 — Record your findings and implement them
- Write down the significant hazards, the people affected, and the controls in place
- A risk assessment must be suitable and sufficient — it does not need to be perfect, but it must be genuine
- Put the controls into practice
Step 5 — Review and update
- Risk assessments should be reviewed regularly and whenever:
- There is a significant change in the work
- An accident or near miss occurs
- A new hazard is identified
The Hierarchy of Control
The hierarchy sets out the preferred order of control measures, from most to least effective:
| Level | Control Measure | Example |
|---|---|---|
| 1. Elimination | Remove the hazard entirely | Design out working at height — use pre-fabricated components |
| 2. Substitution | Replace with something less hazardous | Use water-based paint instead of solvent-based |
| 3. Engineering controls | Physical measures to reduce exposure | Guarding on machinery, local exhaust ventilation, edge protection |
| 4. Administrative controls | Systems of work to reduce exposure | Permits to work, job rotation, toolbox talks, safe systems of work |
| 5. PPE | Personal protective equipment | Hard hats, gloves, high-visibility vests, respirators |
PPE is always the last resort — it protects only the wearer and relies on it being worn correctly at all times. Controls higher up the hierarchy are always preferable.
Risk Rating
Risk is often evaluated using a risk matrix that considers:
- Likelihood — how probable is it that harm will occur? (e.g. 1 = unlikely, 5 = almost certain)
- Severity — how serious would the harm be? (e.g. 1 = minor first aid, 5 = fatality)
Risk rating = Likelihood × Severity
A high risk rating means action is needed urgently. Controls are applied to reduce the likelihood and/or severity of harm, bringing the risk rating down to an acceptable level.
Method Statements
A method statement (also called a safe system of work) is often used alongside a risk assessment. It describes, step by step, how a task will be carried out safely. Together, a risk assessment and method statement are known as RAMS.
Method statements are commonly required for:
- Working at height
- Working near buried services
- Demolition
- Working in confined spaces
- Hot works (welding, cutting)
Exam Practice
2023 Summer — 3 marks
Signage is one control measure used to minimise health and safety risks.
(i) Another control measure is a method statement. Explain the purpose of a method statement. [2]
(ii) State one other control measure likely to be used to minimise health and safety risks. [1]
Mark scheme answer
**(i) Any 2 marks from:** - Detail exactly how to carry out work safely (1) - Describe safety precautions to control risks identified in the risk assessment (1) - Detail equipment to use and PPE required (1) - Break each task into steps and assess hazards in each step (1) - Cover how to dispose of waste safely (1) - Include sequence of planned work, management responsibilities and emergency procedures (1) **(ii) Any one of:** Safe systems of work / Work permits / Competent persons / PPE (1)2022 Summer (S22) — 9 marks
A worker is sawing wood with a circular saw, generating dust and noise, without appropriate PPE.
For each of the following hazards, describe the risk and state an appropriate control measure:
(i) Sawdust/particles near eyes
(ii) Sawdust near lungs
(iii) Noise from the saw
Mark scheme answer
**(i) Eyes** — Risk: Eye injury could occur due to sawdust and wood splinters entering the eye (2). Control measure: Safety glasses / goggles / visor (1) **(ii) Lungs** — Risk: Breathing in sawdust could cause lung disease (2). Control measure: Respirator / dust mask / comfort mask (1) **(iii) Ears** — Risk: Noise from the saw could cause damage to hearing (2). Control measure: Ear defenders / ear plugs / ear muffs (1)2022 Winter — 5 marks
A site boundary is closed off with a plastic mesh barrier, separating an existing school building from the construction site.
Identify two health and safety risks to the school children.
Mark scheme answer
Any two appropriate risks: - Injury or death on site by falls (1) - Crush injury from plant/machinery (1) - Injury through use of equipment (1) - Electrocution (1) - Exposure to hazardous substances (1)2022 Winter — 6 marks
Explain the role of a ‘competent person’ responsible for health and safety on a construction site.
Mark scheme answer
A competent person will: - Demonstrate the required skills, experience, knowledge and understanding of health and safety on site and be able to recognise hazards associated with particular tasks - Apply skills and training to enable tasks to be performed safely - Conduct risk assessments and review method statements prepared by others - Provide site staff with the training, instruction and supervision that each individual requires - Supervise emergency procedures, including the location of emergency equipment - Consider and approve applications for permits to work2021 Winter — 2 marks
Houses from phase one of a development will be occupied before phase two is completed. Children living there may want to explore the active construction site next door.
Identify and explain one health and safety risk to the children.
Mark scheme answer
Any one identified and explained (2 marks): - Injury or death from deep excavations (2) - Accessing machinery/plant which has potential for serious injury or death (2) - Significant danger from trips, slips and falls within the site (2)2022 Summer (Z22) — 2 marks
Identify one health and safety responsibility of:
(i) An employer
(ii) An employee
Mark scheme answer
**(i) Employer (1):** Provide a safe place of work / provide suitable equipment / provide training / provide PPE. **(ii) Employee (1):** Wear PPE provided / report damaged tools or equipment / attend training / take reasonable care for own safety and that of others.2019 Summer — 12 marks
Outline two typical control measures for each situation below and provide a reason for each measure.
Situation 1: Mixing cement by hand
Situation 2: Cutting ceramic floor tiles with an electric tile cutter
Situation 3: Using an industrial saw to cut large timber beams in a workshop