The fan user must consider the effects of the gas and its solid content, on the health of the operators and employees. Most countries have legislation limiting the exposure of employees to substances judged to be hazardous. If the gas to be handled is
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Courtesy of CIBSE (Chartered Institution of Building Services Engineers) — Reproduced from CIBSE Guide C: Reference data
Listed in local regulations the fan manufacturer must be informed. The type of health hazard must be specified.
Another health hazard, sometimes not recognised as such, is noise. Some countries have regulations stipulating the acceptable noise levels and exposure times. It must be remembered that the fan duty will largely determine the fan noise. High pressure fans will be noisier than low pressure fans. System resistance should therefore be kept as low as possible.
Some fan types are inherently noisy. Large equipment, in general, is noisy. Noise levels can be attenuated by fitting acoustic enclosures. However, these tend to drastically diminish the maintainability of the equipment by hindering access. In some instances, costly acoustic enclosures have been removed at site and scrapped in order to achieve acceptable access. One easy solution to this hazard is to declare certain areas “Ear Protection Zones”.
Posted in Fans Ventilation A Practical Guide