QUESTION 1

(a) Describe the principles of

(i) Dilution Ventilation and

(ii) Local Exhaust Ventilation.

(b) What are the essential design features of the component parts of an efficient and cost-effective local exhaust ventilation system?

(c) What examinations or tests would you perform after installation of a local exhaust ventilation system to assess its performance?

QUESTION 2

Describe the main articles contained in the International Labour Organisation
Convention No. C162 on Asbestos (1986). Outline the benefits of having such a standard in the prevention of chemical hazards at the workplace.

QUESTION 3

(a) Describe the factors which should be taken into account when devising a sampling strategy for biological monitoring.

(b) Biological monitoring complements environmental monitoring in the control of toxic substances at the workplace. What are the advantages and limitations of the use of biological monitoring techniques applied to the measurement of occupational chemical exposure in comparison with environmental monitoring methods?

QUESTION 4

(a) What do you understand by the term substance hazardous to health as prescribed under the Occupational Safety and Health Act 2005? Describe the measures that can be taken by an employer whenever an employee uses any substances hazardous to health during the course of his work.

(b) Give a detailed account of the various methods of sampling for gases and vapours in the working environment. Indicate the advantages and disadvantages with the use of each method.