Asbestos cement

• Pages: 37-39

13. Asbestos cement

13.1. Fibre preparation

13.1.1. Where asbestos fibre is supplied in paper or plastic bags, the bags should

be opened and emptied automatically whenever practicable.

13.1.2. If the bags are opened by hand, this should be carried out in the enclosed

booth of a dust extraction system under negative pressure.

13.1.3. The bags should be placed as close as possible to the hopper or feed

chamber.

13.1.4. The contents of the bag should be discharged without the bag being

shaken.

13.1.5. Empty bags should be disposed of immediately within the same dust

extraction system to prevent the release of asbestos dust to the atmosphere.

13.1.6. Where the booth enclosure and exhaust ventilation are insufficient to

prevent the release of asbestos dust to the air of the workplace, the workers present

should wear respiratory protective equipment.

13.1.7. The delivery of the fibre to the storage chamber and any subsequent

weighing and mixing with other materials should be carried out under enclosed

conditions with automatic control.

13.1.8. Exhaust ventilation with negative pressure should be maintained within

the enclosure to prevent leakage of asbestos dust.

13.2. Handling finished products

13.2.1. At the final stage of manufacturing, or wherever asbestos-cement

products are being handled in large quantities, mechanical handling equipment should

be used when practicable.

13.2.2. (1) Individual boards, sheets or other products, when moved manually,

should be placed with care on the stack or other resting site.

(2) Dropping and dragging of finished products should be avoided.

13.2.3. (1) All storage of asbestos-cement products on site should be within a

designated area.

(2) The designated area should be maintained in a clean condition.

13.3. Finishing operations within the factory

13.3.1. (1) All power-sawing, drilling, sanding or milling machines should be

fitted with efficient dust extraction equipment.

(2) Low-volume, high-velocity air systems are usually the most suitable

for this purpose.

37