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Noise is usually seen as a sound that is loud, unpleasant, unexpected or undesired. Sound is what we hear and noise is unwanted sound. Unprotected exposure to harmful levels of noise at the workplace can cause noise induced hearing loss. The occupational exposure limit for noise is 85dB(A) as a time weighted average (TWA) over an 8 hour work shift.

Noise surveys consists of taking noise measurements throughout the workplace to identify noisy areas. Personal noise exposure (noise dosimetry) can also be carried out.

Asbestos in air monitoring is the only way to quantify asbestos in air concentrations. This is done by air drawn through a 25mm mixed cellulose esther membrane (MCE) filter. The filter are then analysed by phase contrast microscopy (PCM) to determine the airborne asbestos concentrations.

Asbestos is the generic name for 6 different naturally-occurring fibrous minerals. A “fibre” is defined as a particle that is more than 5 micrometres (μm) in length and having a length to width ratio of at least 3:1.

Based on their physical and chemical properties, there are two major groups of asbestos: serpentine and amphibole.

Serpentine: Serpentine fibres are long, flexible and curved. These fibres can be woven together. The main type of serpentine asbestos is chrysotile (white asbestos), which is the main type of asbestos used in manufacturing.

Amphiobole: Amphibole fibres are straight and stiff. These fibres are generally brittle and rod- or needle-shaped, which limits their commercial usefulness. There are 5 sub-types of amphiobole asbestos, including:

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azardous chemical substances refers to any toxic, harmful, corrosive, irritant orasphyxiant substance or, a mixture of substances, including dusts, fumes, gases, mists and vapours, that may produce adverse health effects in individuals when exposed to sufficient quantities.

The HCS surveys are carried out according to the Hazardous Chemical Substance Regulations, 1995. (Occupational Health & Safety Act, Act 85 of 1993).

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Lead is a very soft, highly malleable metal that is very resistant to corrosion. In terms of industrial hygiene two categories of lead compounds are considered – firstly, lead and inorganic lead compounds and secondly, organic lead compounds. Lead is widely used in metal products, sheet metal, solders and pigments. It was also widely used as an additive (tetra ethyl lead) in petrol. Other uses of lead include in batteries, pottery glazes and in lead crystal glass. Exposure to lead and inorganic lead compounds usually occurs through inhalation of dust and fume from metal processing, grinding and welding. Lead is readily absorbed through the lungs. Ingestion is also a possible route of entry where poor hygiene standards occur. Once in the body the lead is transported by the red blood cells and stored mainly in the bone marrow where it interferes with haemoglobin production. Organic lead compounds (mainly tetra ethyl lead) are absorbed as a vapour by inhalation and are also readily absorbed through the skin.

The lead surveys are carried out according to the Lead Regulations, 2001. (Occupational Health & Safety Act, Act 85 of 1993)