ATEX ZONE 21 CAT 2D

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Atex Zone 21 Definition

Atex Equipment Zone 21 Category 2D

Safe under normal operation and expected malfunction (dust)

Atex Zone 21 is 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 (from 10hrs to 1.000hrs/365d).

Category 2D explosion proof conversion guarantees an electrical and mechanical protection eliminating any explosion risk for Atex Zone 21 Hazardous Area.

The features include:

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Maximum surface temperature T200° C, T135° C, T100° C

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Dust group IIIA, IIIB, IIIC

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Installation and conversion of components suitable for use in the operating zone

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Monitoring of surface temperatures

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Use of electroconducting materials

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Visual alarm signal

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Load handling device covered with spark-proof material

The use of explosion protection equipment in a potentially hazardous area is a requirement for the Ex supplier and also for the end user in order to be able to work in safety.

The Atex legislation has two different directives and relative requirement, from both the user and supplier of the Explosion-proof equipment in a potentially hazardous area: ATEX 1999/92/EC and ATEX 2014/34/EU.

The Atex legislation directive for industries that operate with potentially explosive atmospheres is the ATEX 1999/92/EC. It requires the companies to prevent the formation of an explosive atmosphere in the workplace, to conduct a hazardous area risk assessment including the valuation of a potential source of ignition and to classify the hazardous area Zones according to the frequency, time and the form in which the explosive atmosphere is present. Atex Zone 21 is classified as high risk area for the presence of powder or dust potentially explosive.

SUMMARY>>> “The ATEX Zones classification”

The workplaces should be classified into hazardous area Zones depending on the frequency and time that an explosive atmosphere is present in the form of gas, vapour, powder or dust:

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ATEX Zone 1 (high risk gas/vapour)

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ATEX Zone 2 (medium risk gas/vapour)

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ATEX Zone 21 (high risk powder/dust)

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ATEX Zone 22 (medium risk powder/dust)

ATEX 2014/34/EU. The user company must place the correct signs at the entry of the area, maintain an explosion protection document and select the Atex explosion proof correct equipment according to the defined zone, compliant with ATEX 2014/34/EU Directive (previously 94/9/EC) which is the directive that defines the requirement for the companies that supply equipment for operation in potentially explosive atmospheres/hazardous areas. Category 2D defines construction requirements for the specific explosion protection level of the Atex zone 21 Hazardous Area.

SUMMARY>>> “The ATEX Categories”

Equipment (as mobile vehicles, special vehicles, engines, compressors, gensets, etc.) for operation in hazardous areas must comply with the requirements of ATEX 2014/34/EU Directive and be flameproof. The level of protection is known as a category which matches the risk:

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Category 2G/Zone 1

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Category 3G/Zone 2

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Category 2D/Zone 21

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Category 3D/Zone 22

Miretti can convert almost all brands of trucks, mobile vehicles for a safe operation in Atex Zone 21 area with many standardized designs.

Combinations of conversions effective against both explosive gas and dust are available according to the Customer’s requirements: Atex Zone 1 + Zone 21 explosion proof conversions.