A hazard is anything the has the potential to cause harm to the health or safety of a person. There are different types of hazards in the workplace such as:

• Chemical:  Gases, vapours, mists, dusts, fibres, corrosives, toxics, irritants, sensitizers
• Physical:  Noise, heat, cold, vibration, light or illumination
• Biological:  Bacteria (e.g. Mycobacterium tuberculosis), viruses (e.g.  HIV), animal products, plant materials
• Radiation:  Ionising, non-ionising, UV, IR, X-rays
• Ergonomic: Manual handling, stretching, standing, posture, display screens, work stations, visibility, repetitive motion
• Psycho-social: Stress, work hours, travel, diet, bullying, excessive expectations, sexual harassment, racial or religious intolerance, culture
• Safety: Trip, slips, falls, electrocution, violence

A risk is the likelihood that this harm will actually occur under the prevailing work conditions and the extent of the effects (consequences).

Examples of workplace risks are:

• Removing asbestos insulation material from inside a factory boiler without the appropriate personal protective equipment
• Manually lifting heavy sacks of material for a large part of the workday
• Operating noisy machinery without hearing protective equipment
• Cleaning xylene spillage using a mop without any personal protective equipment

Continue to a simple model for performing an Occupational Health and Safety risk assessment.