Mine Health and Safety Act, 1996 (Act No. 29 of 1996) Guideline for a Mandatory Code of Practice Occupational Health Programme (Occupational Hygiene and Medical Surveillance) for Noise Part C. Format and Content of the Mandatory COP 8. Aspects to be addressed in the COP

 

Every employer must establish and maintain a system of occupational hygiene measurements and a system of medical surveillance that addresses the following elements:

 

The occupational health programme for noise to be implemented on the mine must be summarised in the COP in a flow chart similar to Figure 1 below.

 

FIGURE 1: Occupational health programme for noise

 

 

The COP should set out measures to ensure that:

NOTE:

Chapter 3 of the handbook by the Safety in Mines Research Advisory Committee (SIMRAC), the Handbook on Occupational Health Practice in the South African mining industry, may be consulted, and any other methodology, to assist in conducting a risk management.

 

The COP must address the points set out below:

At the initial commencement of a system of occupational hygiene measurements, as contemplated in section 12(2) of the MHSA, a baseline risk assessment as contemplated in section 11 of the MHSA is to be conducted to assess the exposure to noise.

The noise baseline risk assessment must as a minimum, address the following:

NOTE:

For the purpose of risk management, the commodity codes (and description), activity codes (and description) and occupational codes (and description) as set out in Annexure A: Mandatory codes should be used.

 

The COP must address the review of the risk  assessment whenever circumstances arise or change at the mine that could have an impact on the original assessments and at least in the following instances:

 

8.1.2        Management of risk

8.1.2.1        Non-significant risk

The employer should put measures in place to ensure that a portfolio of evidence for noise measurements ≥82 dB LAeq, 8h. be established and maintained.

The employer must ensure that a system of noise measurements consisting of area, source and personal exposure monitoring, is implemented for all workplaces with a noise level of  ≥82 dB LAeq, 8h.

 

The COP should  put measures in place to ensure that a hearing conservation programme be established and maintained for all workplaces with a noise level of ≥85 dB LAeq, 8h.

The hearing conservation programme should address the following aspects:

The COP should put measures in place for the development and implementation of a functional structure with clearly defined roles and responsibilities based on the need to coordinate critical activities within the hearing conversation programme.

The  employer  should  establish  a  hearing  conservation  committee  and appoint the following members (but not limited to):

The outcomes of the risk assessment will be utilised as inputs into the hearing conservation  programme.

The COP must address the points set out below:

Step 1

Sub-divide the mine into sampling areas (i.e. surface  = sampling area 1, underground section A = sampling area 2, underground section B = sampling area 3, underground section C = sampling area 4, etc.).

 

Step 2

The sub-division of the sampling areas into activity areas as per the activity area code list found under Annexure A: Mandatory codes which must be complied with.

 

Step 3

Ensure that adequate measurements of personal noise exposures (also refer to paragraph 8.2.1.4.3 below) are taken in line with the identified activity areas. If sufficient historical personal exposure data is not available regarding the extent of the risk, a personal monitoring survey must be undertaken for each identified activity area. Acceptable methodology on personal monitoring as stipulated by SANS 10083 should be used for this assessment.

 

Step 4

A statistical analysis (Annexure B: HEG determination - example of statistical approach is attached for information purposes only) of the personal noise measurement results obtained from the previous sampling cycle, or baseline noise survey for new HEGs, should be conducted as part of the determination and evaluation of HEGs.

 

The results of the statistical analysis conducted for the determination and evaluation of each HEG should be compared to the classification bands for personal noise, tabled in Annexure C: Mandatory classification bands.

 

NOTE:

An activity area e.g. stoping is not a HEG, this activity area i.e. stoping, must be further sub-divided into HEGs.

 

The total number of exposed employees will be determined at the beginning of an annual reporting cycle and would only change if there is an increase in employees during the quarterly reporting cycle (exposed individuals are only counted once in an annual reporting cycle to prevent duplicate counting).

 

NOTE:

In the event where a number of employees changes from quarter to quarter, the employer must indicate such changes in the comments section of the reporting form.

 

Reduction in employees would not reduce the total number of exposed employees during the reporting cycle.

 

The COP should cover the following types of noise monitoring:

8.2.1.4.1 Area noise monitoring

The COP should set out measures to ensure the following:

NOTE:

Personal noise exposure measurement results must not be used for the determination of noise zones.

The COP should set out measures to ensure the following:

NOTE:

Personal noise exposure measurement results must not be used for the determination of noise zones.

The COP should set out measures to ensure the following:

The  COP  must  set  out  measures  to  ensure  a  quality  control  programme  is developed and implemented, taking into account the following, but not limited to:

NOTE:

Refer to Annexure G: Quality assurance for noise measurement and recording.

 

The COP should address the following:

NOTE:

 

To  calculate  the  logarithmic  average  exposure  for  a  given  HEG  or  an occupation I a job category, the equation below should be used:

 

Where:

 

L = the noise levels measured (LAeq) in dBA.

 

n = number of total samples

 

A record keeping system, which records the exposure history of each HEG at the mine, and any other noise monitoring records e.g. calibration certificates, sampling sheets, etc., should be kept and be readily available at the mine, including any reasons for deviation on sample results such as:

 

The COP should stipulate how the hierarchy of controls have been applied as per the hearing conservation programme, considering the following:

 

Sections 13(2) (c) and 17 of the MHSA requires for a system of medical surveillance to consist of an initial medical examination, other (periodic) medical examinations at appropriate intervals, and an exit medical examination.

Regulation 11.4(2) of the MHSA read with sections 11(3) and 11(4) of the MHSA provides that the system of medical surveillance in respect of noise must consist of:

This section details the requirements for audiometric testing procedures to be applied where a hearing conservation programme is required, i.e. where noise control engineering has not been possible or has failed to eliminate the noise hazard.

 

Audiometric testing in the absence of appropriate control measures cannot reduce the risk of NIHL and should not be regarded as a solution to the noise hazard, but as a means of identifying and prioritising problem areas to enable the formulation of appropriate interventions.

 

In conducting audiometric testing, the following should comply with SANS 10083:

 

The employer must conduct audiometric tests at no cost to the employee. The test must be conducted by a registered audiometrist or acoustician, under the supervision of an ENT specialist, OMP or an audiologist.

 

Baseline audiograms should be used to:

 

 

The employee should not be allowed to commence work or enter any noise zones prior to the conclusion of the two audiometric evaluations forming part of the determination of the employee's baseline audiogram.

 

 

When it is not possible to obtain a valid baseline audiometric test result, the test should be repeated within 30 days of employment, or before transfer to a noise zone.

 

 

When it is not possible for the audiometrist, after repeated testing, to obtain a valid baseline test result, the employee should be referred to an audiologist to establish a valid baseline audiogram.

 

NOTE:

The instruction 171 baseline (refer to Annexure H: Instruction 171) that is done on a person entering the mining industry for the first time will be the baseline for the rest of his/her working career.

 

The STS baseline audiograms would have been completed by December 2017, as per the DMRE guidance note for the implementation of STS in the medical surveillance of NIHL. This baseline is repeated at every new employer, because it is used for the purpose of assisting the employer in preventing NIHL.

 

For someone entering the mining industry for the fi.rst time the instruction 171 baseline audiogram may be used as the STS baseline audiogram, at the first employer only.

 

 

 

The employer must conduct periodic audiometric evaluations on an annual basis for all employees having noise exposure levels that equal or exceed 85 dBA. Where employees are exposed to an 8-hour rating level equal to or in excess of 105 dBA, tests should be conducted at intervals not exceeding six months.

 

 

 

8.2.2.5        Exit audiometry

 

Employees' records of medical surveillance must be kept confidential in line with section 15(1) of the MHSA.

 

Ethical standards should be followed by all professionals involved in the hearing conservation programme referred to in this document.

 

Training must include the following:

 

 

Record keeping system

A record keeping system, which records the exposure history of each HEG, and the employee's medical surveillance records should be kept as per the relevant legislative requirements (section 12 and 13 of the MHSA) and these records should be readily available at the mine.

Reporting of the NIHL cases must be done on the DMRE 231 reporting form within 30 days of diagnosis.

All cases of compensable  NIHL must be reported on an annual basis to the DMRE on the DMRE 165 form.

 

This COP must describe a system in place that addresses the linkage between occupational hygiene measurements and the medical surveillance records as contemplated in section 12(3) of the MHSA.

 

For compensation of NIHL refer to instruction 171 (Annexure H: Instruction 171).