Regulation Part 9 - Ventilation and Atmospheric Contaminants

Question 1

The manager is required to appoint a ventilation officer.

(a) Is the manager allowed to appoint more than one ventilation officer?
(b) Who does the manager notify, and by what means?
(c) Who may grant exemption from the requirement to have a ventilation officer?
(d) On what grounds may the exemption be granted?

Answer 1

(a) Yes, the Mine Manager may appoint different ventilation officers for different parts of the mine.
(b) The District Inspector in writing of the appointments.
(c) The District Inspector in writing.
(d) The District Inspector may consider the nature, scale, scope of the mine to not warrant a ventilation officer.

Question 2

(a) What is the manager required to do if there is a risk of exposure to a toxic or asphyxiant substance in excess of the peak or STEL exposure hazard?
(b) What is the manager required to do if the level of an atmospheric contaminant exceeds the peak or STEL exposure standard?

Answer 2

(a) - All persons are removed from the workplace.
- No person may work in the workplace until a suitable written risk assessment has been made.

(b) - Remedy the situation using process, engineering & other atmospheric control measures.
- Supply suitable respiratory equipment conforming to Australian Standards.
- Inform relevant employees of hazard & measures taken to reduce risk.

Question 3

What do the Regulations require with regard to compressed air underground?

Answer 3

• Air compressors draw intake air from the purest source available.
• Air compressors are maintained in good mechanical condition.
• Compressed air mains are fitted with sufficient traps to remove any accumulated oil & water and are drained at regular intervals.
• Air compressors used underground are fitted with a heat sensor that will initiate alarm & shut down at 150 degrees Celsius.
• Diesel engine air compressors used underground are liquid cooled.

Question 4

For the purpose of regulations contained in Part 9 define the following:

(a) Short Term Exposure Limit or STEL
(b) TWA (Time Weighted Average) concentration
(c) Peak in relation to an exposure standard

Answer 4

(a) Short Term Exposure Limit (STEL) means a concentration of an atmospheric contaminant averaged over 15 minutes.
(b) Time Weighted Average (TWA) means a concentration of atmospheric contaminant averaged over a normal 8 hour work period during a 5 day work week.
(c) Peak means the maximum airborne concentration of an atmospheric contaminant determined over the shortest analytically practicable period which does not exceed 15 minutes.

Question 5

The manager of an underground mine must ensure that ventilating air provided for the mine is of sufficient volume, velocity and quality.

What criteria are used to define sufficient volume, velocity and quality of air in an underground mine?

Answer 5

The Mine Manager must ensure that ventilating air for the mine is of sufficient volume, velocity and quality:

• To remove atmospheric contaminants from blasting and other operations.
• To maintain healthy atmosphere in workplaces during working hours by reducing atmospheric contaminants to as low as practicable.

Question 6

List 5 of the duties of the ventilation officer for underground operations.

Answer 6

1. Regularly testing & inspecting workplaces to determine whether:
   - Atmospheric contaminants are as low as practicable.
   - Adequate mine ventilation flows are provided.
2. At 3 monthly intervals and after any subsequent change to the primary circuit, the quantity & quality of the airflows in the mine are recorded.
3. Operating, calibrating & maintaining any metering or monitoring device to measure toxic emissions or other atmospheric contaminants.
4. Ensures all atmospheric contaminant sampling requested by an inspector is carried out.
5. Reading & recording the wet & dry bulb temperatures where it is suspected that temperatures and humid conditions may have an adverse affect on health and safety of a person.

Question 7

When asbestos contamination is found on the mine:

(a) What action must the manager take?
(b) What method should be used to assess the airborne exposure to asbestos?
(c) What dimensions define a countable fibre?

Answer 7

(a) The Mine Manager must ensure:
- Necessary action is taken to protect employees from asbestos.
- Notify the District Inspector in writing.

(b) The method specified in the Guidance Note on the Membrane Filter Method for estimating Airborne Asbestos Fibres.
(c) An object having width <= 1 Um & length >5 Um