Mine Health and Safety Act, 1996 (Act No. 29 of 1996)

Notices

Guideline for the Compilation of a Mandatory Code of Practice for the Prevention of Flammable Gas and Coal Dust Explosions in Collieries

Part C : Format and Content of the COP

8. Aspects to be Addressed in the COP

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The COP must set out how the significant risks identified and assessed in terms of the risks assessment process referred to in paragraph 7.1 will be addressed. The COP must cover at least the aspect set out below unless there is no significant risk associated with that aspect at the mine. The COP must indicate who is responsible for undertaking each task and what should be achieved. See paragraph 1.1 of Part Failure by the employer to prepare or implement a COP in compliance with this guideline is a breach of MHSA.

 

8.1. Preventing the accumulation of an explosive concentration of flammable gas

 

To prevent an accumulation of an explosive concentration of flammable gas, the COP should cover at least the following:

8.1.1. Ventilation of production sections

The ventilation layout for all production sections or changes in ventilation systems should include:

8.1.1.1. Listing of areas of the mine where flammable gas may be present;
8.1.1.2. Sequence of the ventilation related work and respective completion dates;
8.1.1.3. Mining sequence that complements the ventilation flow;
8.1.1.4. The required ventilation controls;
8.1.1.5. Air quantities, velocities and airflow patterns;
8.1.1.6. The approval thereof by the employer, or delegated manager or delegated competent person;
8.1.1.7. Special precautions where two or more sections are situated in the same ventilation district; and
8.1.1.8. Any other special measures to be adhered to such as holing into other areas and barrier pillars sizes.
8.1.2. Mining near or through dykes, burnt coal or geological discontinuities

When mining near or through dykes, burnt coal or geological discontinuities, the COP should describe special measures in addition to the requirements stipulated in 8.1.1, based on but not limited to the following aspects

8.1.2.1. The most appropriate mining methods (drilling and blasting or mechanical mining).
8.1.2.2. The availability of correct geological information.
8.1.2.3. The prevention of dangerous accumulations of flammable gas.
8.1.2.4. Adequate supervision.
8.1.2.5. Suitable monitoring and control of environmental conditions.
8.1.3. Secondary mining

When secondary mining i.e. top/bottom coaling or total extraction methods is applied, in addition to the requirements stipulated in 8.1.1, the COP should describe measures to ensure there is a system for the ventilation of goafs and bleeder roads.

8.1.4. Other areas

The COP should describe measures for the ventilation of underground dams, abandoned areas, accessible seals, workshops, substations, transformers, pump stations, staple pits, shaft bottoms, boxholes, underground and surface bunkers and ancillary workings, which conform to the requirements of 8.1.1.

8.1.5. Intake airways, return airways and belt roads

The COP should describe measures to ensure that:

8.1.5.1. Intake airways, return airways and belt roads remain unrestricted, accessible and that safe roof and side wall conditions prevail; and
8.1.5.2. Adequate air velocities will prevent the accumulation of dangerous gases while preventing dust from becoming airborne.
8.1.6. Main fans

The COP should describe measures to ensure that:

8.1.6.1. Records shall be kept of the operation, monitoring, maintenance and inspection of main and booster fans; and
8.1.6.2. The health and safety of persons who may be affected by the unplanned stoppage of main and booster fans.
8.1.7. Barometric pressure

The COP should describe measures to:

8.1.7.1. Ensure the monitoring and recording of the fluctuations in the barometric pressure; and
8.1.7.2. Be taken to reduce the significant risks associated with such fluctuations.
8.1.8. Abandoned areas

The COP should describe measures to ensure that:

8.1.8.1. Abandoned areas remain ventilated to prevent a build-up of an explosive concentration of flammable gas, or are sealed off;
8.1.8.2. When abandoned areas are being sealed off; the sealing process is in accordance with accepted procedures; ventilation rates are maintained at prescribed levels; stone dust is applied in accordance with the COP and the presence of any flammable gas is monitored continuously until final sealing has been completed;
8.1.8.3. Prior to an abandoned area being sealed off, electrical conductors, earthing and bonding of electrical equipment and accumulations of coal, shall be removed and any borehole sealed off (rehabilitated). Record of these actions shall be kept until mine closure;
8.1.8.4. Working conditions for employees working near abandoned areas are safe; and
8.1.8.5. The monitoring of the atmosphere within the abandoned area is done according to the risk assessment.
8.1.9. Sealed areas

The COP should set out measures to ensure:

8.1.9.1. That containment walls built for containment of flammable gas are provided with the means for the monitoring of the atmosphere behind such walls;
8.1.9.2. The risk posed by walls/seals built before the coming into effect of this guideline in 2002 is addressed;
8.1.9.3. That explosion proof seals are used where the atmosphere of sealed areas stabilises within the explosive range; and
8.1.9.4. Safe working conditions for employees working near sealed areas.
8.1.10. Opening of sealed areas

The COP should set out a procedure for the reopening of sealed areas.

8.1.11. Stoppage, change or reversal in ventilation

The COP should set out a procedure to be followed in the event of a stoppage, noticeable change or reversal in the ventilation. This procedure should include the safe return of persons to the working place after restoration of the ventilation.

 

8.2. Providing for the early detection of flammable gas

 

Refer to applicable and relevant sections of Annexure 1: Guidance note for lamproom practice (for information purposes only).

The COP should set out a procedure for the early detection of flammable gas covering at least:

8.2.1. An appropriate gas testing and gas monitoring strategy including the type/s of instruments to be used;
8.2.2. That employees are competent to test for flammable gasses and dangerous accumulations of any explosive mixture of flammable gasses in accordance with Section 10 (2)(c);
8.2.3. The maintenance, calibration and record keeping in respect of gas testing instruments and gas monitoring systems;
8.2.4. Details of any user’s pre-use tests and checks of the flammable gas warning devices and measuring instruments, including on-board monitoring devices, in accordance with a procedure drawn up by the employer;
8.2.5. Testing for the presence of flammable gas or dangerous accumulations of any explosive mixtures of flammable gasses, identify the frequency, the responsible persons and localities for such testing;
8.2.6. Steps to be followed whenever flammable gas is detected and for the clearance thereof;
8.2.7. The determination of sufficient numbers of gas detection instruments;
8.2.8. The compliance of all specialist flammable gas measuring instruments used for the detection and measurements of flammable gasses with the OEM specification;
8.2.9. Recording and reporting of flammable gas intersections above specified legal limits;
8.2.10. Addressing any unexpected increase in flammable gas emissions and by allocating requisite mitigating actions to competent persons; and
8.2.11. The mine ventilation and rescue plan indicating all known flammable gas sources.

 

8.3. Preventing the ignition of flammable gas

 

Refer to Annexure 2: The guidance note for the prevention of flammable gas and coal dust explosions in collieries (for information purposes only)

The COP should set out measures to ensure that the ignition of flammable gas is prevented, covering at least the following:

8.3.1. The method, frequency and procedure for the examination and changing of cutter picks.
8.3.2. The provision of a continuous flow rate of water and adequate pressure of water supply to mechanical miners.
8.3.3. Control measures to minimise the risk of ignitions from occurring, during goafing considering both partial or total extraction.
8.3.4. Control measures to prevent flammable gas ignitions, that includes operator pre-use checks, operational checks, maintenance programmes, and any other means of preventing a frictional ignition for mechanical miners.
8.3.5. Preventing that the use of electricity or electrical equipment does not create the risk of igniting flammable gas by including procedures covering the following:
8.3.5.1 The use of explosion protected apparatus wherever required in defined hazardous areas (as defined in SANS 1018);
8.3.5.2 Identification of electrical equipment that poses a significant risk and definition of measures to deal with that risk;
8.3.5.3 The interlocking of on board scrubber fans and other electrical equipment used within relevant areas;
8.3.5.4 The positioning of switchgear with respect to prevalent air flow;
8.3.5.5 The performing of flammable gas tests before starting or stopping electrical equipment; and
8.3.5.6 The restoration of electrical power after a power failure e.g. no automatic restarting of fans, safety precautions necessary to prevent a flammable gas ignition, the level of supervision for each activity.
8.3.6 Where lightning could ignite flammable gas, compliance with SANS 10313 Specifications must be considered.
8.3.7 Where spontaneous combustion could ignite flammable gas, measures for the inspection of all work areas and monitoring of abandoned areas and atmospheres behind containment walls must be stipulated.
8.3.8 Where explosives are used, these do not create an additional risk of igniting flammable gas.
8.3.9 Prevention of contraband from being taken underground.
8.3.10 Prevention of flammable gas ignitions when using any welding, flame cutting, flame heating, grinding, vulcanising, soldering, pick sharpening, electronic instrumentation and photography video or audio taping, etc. Measures shall include the following:
8.3.10.1 The training of competent persons to perform such work;
8.3.10.2 Issuing and control of flint lighters;
8.3.10.3 The construction, ventilation, physical characteristics and orderly maintenance of the workshop and cutting bays so that work can be performed in a safe and healthy manner;
8.3.10.4 Precautions to be taken when working outside approved workshops or cutting bays;
8.3.10.5 The ventilation, inertisation, fire prevention and the gas testing procedure before, during and on completion of such work;
8.3.10.6 The precautions and devices utilized to quench flashback and to prevent back feeding of gas;
8.3.10.7 The proper transport, storage and use of gas cylinders and flammable liquid containers; and
8.3.10.8 The issuing, safekeeping and examination of both equipment and devices used.
8.3.11 Prevention of holing excavations into any adjacent area which may contain an accumulation of flammable gas.
8.3.12 Measures to prevent ingress, and ignition of high-pressure flammable gas into existing.
8.3.13 Identification of the potential sources of static electricity and of details related to the prevention and control measures.

 

8.4. Reporting of flammable gas

 

The COP should set out a procedure to ensure that flammable gas intersections are reported. The internal and official reports should describe the recorded presence of any flammable gas concentration exceeding one comma four parts per hundred by volume in the general atmosphere or any ignition of flammable gas as per MHSA Regulation 23.4 (g).

 

8.5. Clearance of flammable gas

 

Refer to Annexure B: The Guidance Note for the Prevention of Flammable Gas and Coal Dust Explosions in Collieries

The COP should set out a procedure to ensure that the clearance of flammable gas accumulations, including roof layers, is done safely addressing at least the following:

8.5.1. The dilution, removal and dispersion of flammable gas, including roof layering;
8.5.2. Isolating electricity; and
8.5.3. Withdrawal of employees.

 

8.6. Limiting the formation and dispersion of coal dust

 

Refer to Annexure B: The Guidance Note for the Prevention of Flammable Gas and Coal Dust Explosions in Collieries

The COP should set out measures for the limiting of the formation and dispersion of coal dust covering at least the following:

8.6.1. Limiting of formation of coal dust at coal mining faces, conveyor belts and transfer points, tramming and travelling routes and any other identified high-risk areas. Such measures must stipulate the design specifications of such dust suppression systems that will be in use on each coal winning or transporting machinery.

 

Note: Such measures should comply with Section 21 of the MHSA.

 

8.6.2. The regular clean-up and removal of coal accumulations in face areas before stone dust applications, as well as along conveyor belt roads and travelling roads, at transfer points, in return airways, on equipment and at any other identified high-risk areas (e.g. decommissioned production panels).

 

8.7. Inertisation of coal dust

 

Refer to Annexure C: Stone Dust Inertisation Standard, Compliance Sampling and Analysis of Samples

The COP should set out measures that will ensure compliance with requirements relating to effective achievement of coal dust inertisation at least as set out in Annexure C which include:

8.7.1. Inertisation of coal dust by using water;
8.7.2. Inertisation of coal dust by the application of stone dust;
8.7.3. The extent of stone dust application;
8.7.4. Estimating qualitatively the degree of in-situ inertisation achieved; and
8.7.5. Frequency for the application of stone dust.

 

8.8. Compliance with requirements relating to sampling and analysis of samples

 

The COP should set out measures to ensure that compliance with requirements relating to sampling and analysis of stone-dust samples is achieved covering at least the content as set out in Annexure C.

 

8.9. Compliance with requirements relating to the design of barriers to prevents the propagation of coal dust explosions

 

The COP should set out measures to ensure that compliance with requirements relating to the design of explosion propagation barriers to prevent the spread of coal dust explosions is achieved based on at least the contents of Annexure D.

 

8.10. Explosions in pit, tank, vessel, container or chamber likely to contain noxious or flammable fumes or gases or an atmosphere deficient in oxygen

 

The COP should set out measures to prevent the accumulation and ignition of flammable gas and/or explosive mixtures in confined spaces on surface such as beneficiation plants, silo's, containers and bunkers must be stipulated.