A legal obligation lies on those responsible for cleaning up industrial dusts and other materials within manufacturing processes. Here, specialist in commercial cleaning equipment Nilfisk provides an overveiw of the legal requirements and solutions available.
For employers and cleaning companies failure to comply with current standards can lead to loss of life, serious injury and extensive damage to property. Heavy fines can be levied against those who put their employees at risk by failing to carry out adequate risk assessments.
Modern industry deals with an ever increasing variety of materials in a variety of working conditions. Some of these materials in dust form are known to be hazardous to health; other materials may not be thought of as a health hazard but could, in the right circumstances, prove lethal if cleaned up using the wrong equipment. Some of the cleaning machines may have to work in hazardous areas caused by the presence of flammable vapours or gases and so should be constructed accordingly to the relevant standards.
If the material being collected in a vacuum cleaner is combustible it will be mixed with large amounts of air within the vacuum cleaner. This will form a cloud of dust and vapours inside the machine.
All that is then required to produce an explosion is an ignition source. Vacuum cleaners produce static electricity as the dust passes through the machine. Conventional vacuum cleaner motors also produce sparks from carbon brushes. The three necessary elements to produce an explosion are therefore present within the machine and a serious incident could result. Fortunately these risks have long been recognised and technical solutions found which remove the risk of ignition. Machines for combustible dusts are constructed in such a way that static electricity is safely routed to earth and the motors used do not create sparks. Additional standards apply to the construction of machines required to work in atmospheres which are hazardous due to the presence of flammable gases or vapours.
The employer has legal duties under the ATEX 137 Directive to conduct a risk analysis on their processes (which includes cleaning) and to then select ATEX approved equipment intended for use in high risk areas. The employer also has duties under the Dangerous Substances and Explosive Atmospheres Regulations 2002 that specifically include implementing control measures and providing equipment which will reduce the quantity of dangerous dusts and prevent explosive atmospheres.
Industrial vacuum manufacturer Nilfisk-CFM has developed safety vacuum cleaners that are specifically designed for the collection of combustible dusts.
These safety vacuum cleaners are submitted to specially Notified Bodies for testing and ATEX certification for equipment within potentially explosive atmospheres.
The ATEX approval will be specific to the category of equipment and nature of the risk (combustible gas, vapour or dust etc) considering the particular hazardous zone etc. (e.g. Zone 21, Zone 22, Zone 1 or Zone 2.)
Hazardous places are classified in terms of zones on the basis of the frequency and duration of the occurrence of an explosive atmosphere.
Zone classifications
For gases, vapours and mists the zone classifications are: Zone 0 – A place in which an explosive atmosphere consisting of a mixture with air of dangerous substances in the form of gas, vapour or mist is present continuously or for long periods.
Zone 1 – A place in which an explosive atmosphere consisting of a mixture with air of dangerous substances in the form of gas, vapour or mist is likely to occur in normal operation occasionally.
Zone 2 – A place in which an explosive atmosphere consisting of a mixture with air of dangerous substances in the form of gas, vapour or mist is not likely to occur in normal operation but, if it does occur, will persist for a short period only.
For dusts the zone classifications are: Zone 20 – A place where an explosive atmosphere in the form of a cloud of combustible dust in air is present continuously, or for frequent long periods.
Zone 21 – A place in which an explosive atmosphere in the form of a cloud of combustible dust in air is likely to occur in normal operation occasionally.
Zone 22 – A place in which an explosive atmosphere in the form of a cloud of combustible dust in air is not likely to occur in normal operation but, if it does occur, persist for a short period.
Machines are available to collect hazardous materials yet work safely within either non hazardous or certain hazardous ATEX zoned areas caused by the presence of flammable gases, vapours or combustible dusts.
