Risk Assessment and Management

Faisal Al Hadad

Consultant of Family Medicine & Occupational Health

PSMMC

Hazard vs. Risk

Hazard is any source of potential damage, harm or

adverse health effects on something or someone under

certain conditions at work.

Risk is the chance or probability that a person will be

harmed or experience an adverse healtheffect if exposed

to a hazard.

Classification of aerosols

Dusts solid particles made airborne by mechanical disintegration of bulksolid material e.g. cutting, grinding, abrasion, crushing, handling,transportation

Inhalable dust is fraction of total airborne particles that are inhaled throughthe nose and or mouth e.g. wood dust, cement dust, flour dust

Respirable dust is fraction of total airborne particles that penetrate theunciliated airways of the lung (alveolar region) where gas exchange occurse.g. silica, coal dust

Fibres: respirable fibre is defined as a fibre >5 µm in length, with a lengthto width ratio of at least 3:1 and a diameter <3 µm e.g. asbestos, machineMade mineral fibre

Classification of aerosols

Fumes formed when material from a volatilized solid condenses in cool aire.g. rubber fume, diesel fumes, welding fume

Mists are suspended liquid droplets generated by condensation of liquids fromthe vapour back to the liquid state or by breaking up a liquid into dispersedstate e.g. paint spraying mist, oil mist Gases are formless fluids which expand to occupy the space or enclosure inwhich they are confined e.g. CO

Vapours are volatile forms of substances that are normally in the solid orliquid state at room temperature and pressure e.g. toluene

Risk Assessment

Definition:

RA is a structured and systematic procedure, which is

dependent upon the correct identification of hazards and

an appropriate assessment of risks arising from them for

purposes of their control and avoidance

(HSE, 1995)

Risk Assessment

Purpose of risk assessment: to enable a valid decision to bemade about measures necessary to control exposure tosubstances hazardous to health arising in any workplace

Process of risk assessment1. Hazard identification2. Exposure assessment 3. Risk characterization

Hazard identification

Definition: hazard identification is determining the presence andcharacteristics of contaminants that affect human health

Methods: Accident and ill health statistics Investigation of accidents, ill health effects and complaints Audits Workplace inspections (walk-through survey) List of the chemicals purchased and used (MSDS) Understanding the process in order to determine the intermediate and final

products Brain-storming of those who work in specific areas

Exercise: Hazard identification

Exposure assessment

Definition: exposure assessment is determining the

conditions of exposure and the doses received by those

exposed

Methods: Workplace inspections Industrial hygiene surveys (e.g. sampling, noise survey)

Biological monitoring

Risk characterization

Definition: risk characterization estimating the likelihood

of an adverse health outcome in exposed populations

and the uncertainties associated with the estimate

Level of risk intolerable tolerable negligible

Risk Management

Definition: risk management is the eradication or minimization of theadverse effects of the pure risks to which an organization is exposed(Bamber, 1990)

Purpose : to prevent injuries and ill health from hazards

Process: Prevention and control Risk communication Health surveillance

Prevention and control

Organizational solutions

Engineering solutions

Use of personal protective equipments

Organizational solutions

Complete elimination of the process that leads to the exposure

Complete elimination of the substance (s) causing the risk

Substitution by a less toxic substance

Substitution by the same substance, but in a form that reduces the risk of exposure

Designing or redesigning the process so that exposure is minimized

Suppressing the substance

Engineering solutions

Total enclosures under negative pressure

Partial enclosures with extract ventilation

Extracted canopies

Hood or slots

General or dilution ventilation

Use of personal protective equipments

Respiratory protective equipment (e.g. respirator, breathing apparatus)

Hearing protectors (earmuffs/earplugs)

Gloves/sleeves

Protective clothing (e.g. jacket, trousers, aprons, overalls, coveralls, body suits)

Eye and face protectors (e.g. safety spectacles, goggles, face shields or visors)

Risk communication

Risk communication is communicating information

on risks to the stakeholders

Communication on risk should aim to bridge the gap

between perceived risks and real risks

Health surveillance

Definition:The periodic medicophysiological examination of exposed workerswith the objective of protecting and preventing occupationallyrelated diseases (Notten et al, 1986)

Rationale: to detect adverse health effects from occupational exposures at asearly a stage as possible

Indications of health surveillance

Where the RA indicates that it is required or it meets the following criteria:

An identifiable disease or adverse effect is associated with the work activity

Appropriate methods are available to identify such ill effects

It is reasonably likely that the adverse effect will occur giving the prevailing work conditions

HS will offer additional protection to the workforce's health

Methods of health surveillance

Symptom review

Clinical assessment

Medical examination

Special investigations (lung function tests, audiometry, chest x-rays, bladder cytology, periodic eye tests)

Determination of immune status (anti-HBS, tuberculin testing)

Biological monitoring (blood, urine, expired air samples)