Typical Examination Questions based on Element 8

``1.	Outline the factors that may affect the efficiency of a local exhaust ventilation (LEV) system.	(8)
	Factors can include: Blocked filters. Hood placed too far from source of contaminant. Lack of maintenance and testing. Unauthorised alterations. Wear or corrosion of fan blades. Incorrect settings. System overwhelmed by increase in contaminant. Inadequate design
2.	Identify the information that should be included on a hazard data sheet supplied with a hazardous substance.	(8)
	Information should include: The name of the substance. It's chemical properties and composition. The nature of hazards. Relevant standards (e.g. Occupational exposure limits). Precautions to be observed in its transport, handling and use. Measures to take in an emergency (e.g. spillage or accidental exposure) including first-aid treatment and disposal requirements.
3.	a) List the elements of a hierarchy for the control of airborne contaminant (b) Outline TWO reasons why a cartridge-type respirator may in practice fail to provide a sufficient level of protection.	(6) (2)
	Control measures in correct order of use are: Elimination of the substance or its substitution with something less harmful. Possibility of reducing exposure by introducing changes in working methods (e.g. use of brush instead of spray or, pellets instead of dust), or to work patterns. Segregation or enclosure of the process and provision of LEV). Lastly, the provision of PPE. Reasons include: Poor fit of the respirator, either because of the use of other PPE at the same time or facial hair. The use of incorrect cartridge. The cartridge not being properly fitted. Failure to change the cartridge at appropriate intervals. Inadequate storage facilities leading to respirator being damaged or contaminated.
4.	(a) Describe the typical symptoms of occupational dermatitis. (b)State the factors that could affect the likelihood of dermatitis occurring in workers handling dermatitic substances. (6)	(2) (6)
	Symptoms are reddening, blistering and cracking of the skin with a possibility of infection and ulceration. Factors include; the nature of the agent, concentration levels and the duration and frequency of exposure when dermatitis substances are handled. Additional factors that could increase the risks include cuts and abrasions that would allow the chemical to be absorbed more readily. Existing skin conditions, the type of skin and its sensitivity, the specific site of skin contact, poor personal hygiene and the misuse of protective measures are other factors
5.	Outline the Factors to be considered in the selection of respiratory equipment for persons carrying out welding activities
	Factors to be considered include: The nature and concentration of contaminants released from the welding process. The material to be welded including any surface coatings (eg lead paint) and the constituents of the filler materials must all be assessed. Once this has been done a range of suitable respiratory protective equipment that would offer adequate protection can be considered. In doing so consideration would be given to the compatibility of the equipment with the work to be done and any other PPE, ergonomic considerations (Bulkiness, comfort etc.), the level of training required, the duration and use, the ease of maintenance and the costs
6.	(a) Define the term 'target organ' within the context of occupational health. (b) Outline the personal hygiene practices that should be followed to reduce the risk of ingestion of a hazardous substance.	(2) (6)
	(a)Target organs are , the organs of the human body upon which a toxic material exerts it effort. (b) Personal hygiene practices would include, washing hands before eating , the avoidance of eating or drinking and smoking in the workplace, utilising facilities for contaminated clothing, appropriate use of gloves and avoiding hand to mouth contact