Skip to 0 minutes and 1 secondHealth effects relating to dust exposure depends on the type of dust, how long and how often a worker is exposed, as well as the exposure level. Visible dust is coarse, while the finer particles cannot be seen with the naked eye. Thus, the human eye is not a reliable guide to assess exposure to dust in the working environment.
Skip to 0 minutes and 26 secondsIt is possible to measure airborne dust. Samples from the workplace atmosphere can be used to measure the concentration of dust in the air as well as give information about the components of the dust. The two most frequently used methods for such air pollution sampling are personal sampling and stationary sampling. In this film you will see someone undertaking personal sampling in a coffee factory. Air samples to determine personal exposure are preferably collected in the worker's breathing zone. The concentration of the pollution in this area is believed to be representative of the pollution in the inhaled air. The equipment used for dust sampling in the workplace atmosphere includes a pump, a flow meter and filter cassette with filters.
Skip to 1 minute and 21 secondsDust in the air is collected on the filter during the sampling period. After sampling is completed, the quantity of dust is determined by weighing the filters in the laboratory. It is also possible to identify the elements present, but this kind of analysis requires special laboratory resources.
We have just shown you a film from a coffee factory where airborne dust was sampled from the workplace atmosphere by using the personal sampling method.
Exposure information on all exposed workers is desirable, but not practically possible. Therefore, a strategy has been developed based on grouping workers who are believed to have similar exposures. Measurements conducted on a representative worker from each group are considered applicable for all members of this group. Thus, where grouping is possible, an overall workplace analysis is possible based on a few measurements from representative samples.
When doing stationary sampling the sampling equipment must be fitted at fixed sampling locations in the workplace or work area. Stationary measurements are therefore not suitable for workers with a mobile work pattern. They are, however, useful for mapping background exposure levels in the workplace.
Stationary measurements can also be used for work place atmosphere surveillance. Instruments that provide direct readings are examples of this type of surveillance. They have the advantage of being able to be connected to warning systems, and thus can give signals when a given concentration limit is exceeded.
© University of Bergen. Video: Frode Ims/Tane Høisæter. Author: G. Tjalvin.