Precautions to reduce health risks in concrete work

2019-06-18T09:46:58+00:00June 19th, 2019|News|

As with many other materials, there are potential risks involved in handling or working with Portland cement or mixes made using Portland cement.

Here Bryan Perrie, MD of The Concrete Institute, provides guidance on how to avoid the effects of unprotected exposure.

The composition of Portland cement is such that when dry cement is exposed to water a chemical reaction called hydration takes place, releasing a very strongly alkaline (and caustic) fluid. This can cause alkali burns and safety measures should be observed. Appropriate precautions are advised to prevent tissue damage when handling fresh mixes containing water and Portland cement.

Cement dust, dusts from handling aggregates and from cutting concrete are easily inhaled, therefore prolonged or regular exposure to these dusts should be avoided.

Portland cement is a complex combination of compounds that includes minute quantities of trace elements. Although South African cements typically contain less than two parts per million of Hexavalent Chrome (widely regarded as a safe level), it may serve as an aggravating factor in cases of exposure to alkaline fluids. There have been some reports of allergic dermatitis after exposure to these fluids.

When fresh concrete or its bleed water comes into contact with human skin, the alkalis react with the oils and fats in the skin as well as the proteins in the skin itself causing tissue damage. Other organic tissue (for example, mucous membrane) can also be attacked by strong alkalis leading to burns that can sometimes be severe, and users should try to avoid all unnecessary contact with these fluids. Where such contact is unavoidable, suitable precautions should be taken.

Roughness and dryness of the hands after working with concrete is a typical consequence of loss of these oils and fats. More prolonged exposure could result in irritant dermatitis and it is possible that the effects of trace elements may aggravate the condition and lead to an allergic dermatitis. To safeguard against accidental exposure, appropriate protective equipment is strongly recommended.

Impermeable gauntlet type rubber gloves and high length rubber boots should be worn to prevent direct contact with skin. Trousers should overlap the boots rather than be tucked into them.

Hydrophobic alkali-resistant barrier creams should be applied to hands and any areas of skin likely to be in contact with fresh concrete; ordinary barrier creams are likely to be inadequate.