Fall Out Monitoring
Fall-out dust monitoring is a legal requirement under the pollutions act of 1975. The act states that '......', and this means that all manufacturing concerns are responsible for the dust at the perimeter of the area. If the dust levels measured are above the specified limits then engineering solutions need to be implemented to decrease the fall-out dust levels.
- Rainfall, because dust is attracted to the water vapour in the atmosphere and it then precipitates along with the rain.
- Wind, because dust is carried by the wind and will only fall-out when there is absolutely no wind.
- Geographical features (take comma away) or any other factor that could influence the rainfall or the wind, for reasons mentioned above.
- Pollens and small insects because these add to the dust levels and precipitate out in the same way.
- 'Dusty activities' (the most influential factors) such as dropping material from a conveyor onto a pile without considering the fall height. This and countless other activities are necessary in the mining and other industries and the challenge, once dust problems are detected, is to engineer them away.
Generally finer suspended dust (2.5µm > 10µm) will remain airborne almost indefinitely due to the dynamic nature of the air currents and thermal activities on any given day, even if there is no wind at all. Particulate larger than this range will settle on a very still day and this material can be collected.