Westwood Security Shutters Ltd have added a range of Atex approved three phase motors to their leading UK range of roller shutters and fire shutters.
When fitting a roller shutter under conditions considered potentially combustible, or where a slight possibility of an explosion is present, Westwood Secure recommend using ATEX asynchronous type motors in any roller shutters or fire shutters installed. These motors are a sealed unit whch is beneficial in the aforementioned conditions – defined as an “explosive atmosphere”. This type of atmosphere features a mixture of air, with flammable substances in the form of gas, steam, mists or dusts in which, after the prime, the combustion propagates together with the mixture not burned.
Directive 99/92/CE fixes a minimum prescription to better protect of the safety and the health of employers that operate under an explosive atmosphere risk.
The electric motors used in our automatic roller shutters can be supplied to conform with the Atex legislation which applies to business that require risk assessments to determine the likelihood of explosions or fires in the workplace or in storage facilities. Westwood Security are able to supply roller shutters that conform with the required standards.
Dangers emanating from static electricity and from electrical sparking from an unprotected motor are recognised under both UK Health & Safety legislation and also by the European Union. The latter has recently thrown its weight behind an initiative to deliver higher levels of safety in plants where explosions during manufacture or storage are a threat. Since summer 2011 ATEX certification has been mandatory for processing plants.
The key element of ATEX certification is a risk assessment and factories now require an Explosion Protection Document, which can be requested by Health and Safety Executive inspectors.
The term ‘ATEX’ is derived from the French Atmospheres Explosive. More specifically the Department of Trade and Industry (DTI) implemented ATEX 95 under The Equipment and Protective Systems for Atmospheres Regulations, 1996 (EPS). ATEX concerns the supply of equipment, protective systems, components etc, where these are for use in potentially explosive atmospheres. The DTI is responsible for policy issues, resolution of supply issues at EU level, appointing Notified Bodies in the UK, etc.
The user directive, ATEX 137, is implemented by HSE under The Dangerous Substances and Explosive Atmosphere Regulations, 2002 (DSEAR). ATEX 137 concerns worker health and safety in those workplaces where potentially explosive atmospheres may be present. The Regulations are enforced in Britain by the HSE, and in some circumstances by other bodies such as Local Authorities and Petroleum Licensing Authorities. The Directive gives indications on the Division of the areas in which potentially explosive atmosphere can develop.
The areas at risk of explosion are divided into zones depending on the frequency and the duration of the presence of explosive atmosphere and to the type of dangerous substance, more precisely:
Zone 0: area in which the presence of an explosive atmosphere, made of a mixture of air and flammable substances as gas, steam, mists, is permanent, or it lasts for a long period or it happen frequently.
Zone 1: area in which, during regular activities, is probable the development of an explosive atmosphere made of a mixture of air and flammable substances as gas, steam and mists.
Zone 2: area in which during regular activities, it is not probable the development of an explosive atmosphere made of a mixture of air and flammable substances as gas, steam or mists, and when, even if that happen, is just for a short term.
Zone 20: area in which the presence of an explosive atmosphere, in the form of a cloud of combustible dust in the air, is permanent, or it lasts for a long period or it happen frequently.
Zone 21: area in which occasionally, during regular activities it is probable the development of an explosive atmosphere in the form of a cloud of combustible dust in the air.
Zone 22: area in which during regular activities it is not probable the development of an explosive atmosphere in the form of a cloud of combustible dust and, even if that happen, it is for a short term.
Besides the classification of the work-area it must be defined other two basic parameters to execute an ATEX
analysis, i.e. the group membership of the equipments that is divided in:
Group I: it includes the systems that will be use in the underground caves and in their installation on the surface,
exposed at the risk of firedamp and combustibles dusts release.
Group II: it includes the systems that will be use in environment where explosive atmospheres are probable.
The Classification data’s of the areas at risk of explosion allow classifying the systems in the following categories:
Category 1: it includes the products designed to work and to guarantee the level of protection requested even in case of exceptional failure of the device. In case of failure of one of the protection devices, at least one independent device assures the level of protection requested. In case of two different failures, one independent from the other, the level of protection requested is guaranteed.
Category 2: includes products designed to function and guarantee a high level of protection to work in environment where there is the probability that explosive atmosphere can develop. That can happen for the presence of gas, steam, mists or air and dust explosive mixture.
Category 3: includes products designed to work and guarantee a regular protection level to work in environment where there are scarce probability that explosive atmospheres due to the presence of gas, steam, mists or air and dust mixtures, can appear, and even if that occur, it is for a short term.
Another basic data is the maximum surface temperature allowed. In case of use in areas with dangerous potentially explosive atmosphere it must be verified the suitability of the motor in the classification of the zone and to the flammable substances that are in the system. The essentials safety requirements against the risk of explosion in the classified areas are fixed by the European Directives:
For additional information please Contact Westwood and we will be pleased to advise further..