ND Unit A - Element A4: Identifying Hazards, Assessing and Evaluating Risks Flashcards
What uses might we have for accident and ill- health data?
Accident and ill-health data may be used to:
• Classify industries according to risk.
• Classify workplaces.
• Classify occupations.
• Consider accident trends.
• Consider parts of the body injured - use of protective clothing.
• Determine hazards in a workplace by using ‘cause of injury’.
• Consider where the fault lies.
• Measure the effect of preventive/control measures.
What internal information can organisations use to help in the assessment of risk?
Useful internal information sources when assessing risk include:
• Accident and ill-health reports.
• Absence records.
• Maintenance records, which usually show damage incidents.
Explain the difference between “incidence” and “prevalence” when referring to accident or ill- health statistics.
Incidence indicates the number of new cases in a population in relation to the number at risk, whereas prevalence indicates the proportion of persons in a given population who have a defined (usually ill-health) condition.
Giving two examples for each, identify the “4 Ps” recommended by the HSE when preparing a checklist for inspections.
The “4 Ps” include: • Premises, including: – Access/escape. – Housekeeping. – Working environment. • Plant and substances, including: – Machinery guarding. – Local exhaust ventilation. – Use/storage/separation of materials/chemicals. • Procedures, including: – Permits-to-work. – Use of personal protective equipment. – Procedures followed. • People, including: – Health surveillance. – People’s behaviour. – Appropriate authorised person.
What are the characteristics of a suitable and sufficient risk assessment?
Characteristics of a suitable and sufficient risk assessment:
• It should identify the significant risks arising from, or in, connection with the work.
• The detail in the assessment should be proportionate to the risk.
• Whenever specialist advisers are used, employers should ensure that the advisers have sufficient understanding of the particular work activity they are advising on; this will often require the effective involvement of everyone concerned.
• Risk assessments should consider all those who might be affected by the activities, whether they are workers or others, such as members of the public.
• The risk assessment should indicate the period of time for which it is likely to be valid.
What is a tolerable risk?
A tolerable risk means that we, as a society, are prepared to endure it because of the benefits and that further risk reduction is grossly out of proportion in terms of time, cost, etc.
The frequency of pipework failure in a large LPG storage facility is estimated at once every 100 years
The starting point is to logically construct an event tree
Outline the basic principles of a Hazard and Operability Study.
Hazard and Operability Studies are designed for dealing with complex systems, e.g. a large chemical plant. They are carried out by a multidisciplinary team that makes a critical examination of a process to discover any potential hazards and operability problems. A series of guide words are applied to each part of the system to identify the possible consequences of a failure.
Briefly explain the difference between an “event tree” and a “fault tree”.
A fault tree identifies the sub-events that are necessary to cause a specified undesired event, such as an accident. Logic gates are used to show how the sub-events combine together to cause the undesired event.
An event tree is used to identify the possible outcomes following an undesired event.
Both techniques may be used qualitatively and, if suitable data is available, quantitatively.
Explain formulas for Incidence, Frequency, Severity and Prevalence rates
Incidence = total injuries x 1000
divided by number of employees
Frequency = total injuries x 100,000
divided by total hours worked
Severity = total days lost x 1000
divided by total hours worked
Prevalence = total cases in population x 100
divided by total population
List principles of prevention as per MHSW Reg 4 and Schedule 1
avoid risks evaluate risks which can't be avoided combat risks at source adapt work to man adapt to technical progress replace dangerous with non/less dangerous develop overall prevention policy give collection protective measures priority over individual provide instruction to employees
What AIR, AFR, ASR, and, how do you calculate these?
AIR = Accident Incidence Rate AFR = Accident Frequency Rate ASR = Accident Severity Rate
AIR = no. accidents / no. employees x 1000 AFR = no. accidents x 100,000 / hours worked ASR = no. days lost x 1000 / hours worked
