Explanations for product markings found on ATEX approved equipment. ATEX is the regulatory directive for the design, installation and use of products in environments where there is a potential explosion risk from flammable gases or dust that are or could be present in the surrounding air.
For more in-depth information on the ATEX directive we suggest you visit the UK Health and Safety Executive or the European Union Commission. To get a product ATEX approved we suggest contacting SGS Baseefa or SIRA in the UK.
- Product Label Markings
- ATEX Coding
- Certificate Number
- Combustible Flyings
- Conductive Dust
- Dust Groups
- Electrical Parameters
- Electrical Protection Concepts
- Encapsulation (m)
- Enclosed Break (nC)
- Enclosure (t)
- Energy Limited (nL)
- Entity Rating
- Equipment Category
- Equipment Group
- Equipment Protection Level
- Flameproof (d)
- Gas Groups
- Increased Safety (e)
- Ingress Protection
- Intrinsic Safety (i)
- Manufacturer Name and Address
- Non-Conductive Dust
- Non-Sparking (nA)
- Notified Body Identification Number
- Oil Filled (o)
- Powder Filled (q)
- Pressurised (p)
- Product Identification
- Restricted Breathing (nR)
- Surface Temperature
- Surface Temperature with Dust Layer
- Serial Number
- Temperature Class
Product Label Markings
Please click on an example marking below to be guided to the related glossary item:
- ATEX Coding (e.g. Ex II 1 G)
- Gas (e.g. Ex ia IIC T4 Ga)
- Dust (e.g. Ex ta IIIC T135°C 85°C Da IP65)
- Ambient Temp (e.g. Tamb -20°C to +60°C)
- Cert No. (e.g. TUV03ATEX2006X)
- Notified Body (e.g. 0044)
- Yr / Serial No. (e.g. 2010 SN: 888888)
- Electrical (e.g. Output: 4-20mA Excitation: 14-28Vdc, Vs+: pin 1 Vs-: pin 2 GND: E)
- Entity Ratings (e.g. Ui: 28Vdc Li: 93mA Pi: 660mW)
- Manufacturer (e.g. XYZ Sensors, City, Postcode, Country)
- Product (e.g. Type: XYZ Pressure Transmitter)
Defines the equipment group and category for flammable gas and/or dusty environments, i.e. Ex I M1, Ex I M2, Ex II 1 G, Ex II 1 D, Ex II 1 GD, Ex II 2 G, Ex II 2 D or Ex II 2 GD.
A unique number issued with an ATEX certificate for a particular product or group of products. A certificate number is issued by a Notified Body such as SGS Baseefa (UK), SIRA (UK), TUV (Germany) or CESI (Italy) following the certification process.
Material, fibres and flyings produced by machinery found in industries such as textile, cotton and wood cutting which settles around equipment and is vulnerable to ignition from heat or sparks.
Metal particles such as Aluminium or Titanium that are deposited on equipment as dust layers and form as dust clouds in the local atmosphere.
Type of combustible dust present in the atmosphere:
Specifies the type of input and output characteristics of the product, including configuration of pin or wiring connections.
Electrical Protection Concepts
Describes the type of protection which has been incorporated into the design:
- d – Flameproof:Gas zone 0
- pxb – Pressurised: Gas zone 1
- pyb – Pressurised: Gas zone 1
- pzc – Pressurised: Gas zone 2
- p – Pressurised: Dust zone 21 or 22
- ia – Intrinsic Safety: Gas zone 0 or Dust zone 20
- ib – Intrinsic Safety: Gas zone 1 or Dust zone 21
- ic – Intrinsic Safety: Gas zone 2 or Dust zone 22
- nA – Non-Sparking: Gas zone 2
- nL – Energy Limited: Gas zone 2 (n.b. no longer specified on new approvals)
- nR – Restricted Breathing: Gas zone 2
- nC – Enclosed Break: Gas zone 2
- ma – Encapsulation: Gas zone 0 or Dust zone 20
- mb – Encapsulation: Gas zone 1 or Dust zone 21
- mc – Encapsulation: Gas zone 2 or Dust zone 22
The electrical components of a product are encapsulated with a material that isolates them from a surrounding explosive environment so that it cannot be ignited.
Enclosed Break (nC)
Electrical devices which include circuit breakers or switches are enclosed so that any explosion of flammable gas inside the enclosure is contained without damaging components or allowing it to pass outside into the surrounding flammable atmosphere.
The product is placed inside a box which provides a dust free environment. The surface temperature of the box must not ignite the surrounding atmosphere.
Energy Limited (nL)
(n.b. no longer specified on new approvals)
Electrical circuits are designed to prevent sparks and temperatures exceeding limits which might ignite an explosive atmosphere.
The maximum safety specific electrical values that must not be exceeded by equipment connected to the product:
- Ui – Voltage
- Ii – Current
- Pi – Power
- Li – Inductance
- Ci – Capacitance
Indicates the level of safety protection a product must perform to:
- M1 – Mining: Energised
- M2 – Mining: De-energised
- 1 – Non-Mining: Very High Protection – Equipment must be safe during regular functioning, likely and infrequent failures, required for Gas zone 0 and/or Dust zone 20
- 2 – Non-Mining: High Protection – Equipment must be safe during regular functioning and likely failures, required for Gas zone 1 and/or Dust zone 21
- 3 – Non-Mining: Normal Protection – Equipment must be safe during regular functioning, required for Gas zone 2 and/or Dust zone 22
Used to distinguish between applications in mines and other areas:
- I – Mining
- II – Non-Mining
Equipment Protection Level
Shows the level of explosion risk and type of atmosphere that a product has been approved for:
- Ga – Gas zone 0
- Gb – Gas zone 1
- Gc – Gas zone 2
- Da – Dust zone 20
- Db – Dust zone 21
- Dc – Dust zone 22
- Ma – Energised
- Mb – De-energised
Explosive atmosphere symbol for European Union countries
The product incorporates mechanical features which are designed to contain an explosion and not allow any flame to escape.
Type of flammable gas present in the atmosphere:
- I – Methane (mining only)
- IIA – Propane (less easily ignited)
- IIB – Propane
- IIC – Hydrogen (more easily ignited)
Increased Safety (e)
Equipment is designed and manufactured with components which prevent ignition sources being generated internally such as static discharges or high temperatures.
States how well the product will prevent dust and moisture entering the interior of the product case or enclosure:
- IP54 – Limited dust ingress protection, Protected against water spray from any direction
- IP55 – Limited dust ingress protection, Protected against low pressure water jets from any direction
- IP56 – Limited dust ingress protection, Protected against high pressure water jets from any direction
- IP57 – Limited dust ingress protection, Protected against temporary immersion between 15cm and 1m depth
- IP58 – Limited dust ingress protection, Protected against long term immersion to a specified depth
- IP64 – Total dust ingress protection, Protected against water spray from any direction
- IP65 – Total dust ingress protection, Protected against low pressure water jets from any direction
- IP66 – Total dust ingress protection, Protected against high pressure water jets from any direction
- IP67 – Total dust ingress protection, Protected against temporary immersion between 15cm and 1m depth
- IP68 – Total dust ingress protection, Protected against long term immersion to a specified depth
Intrinsic Safety (i)
Equipment will limit the amount of electrical energy entering a hazardous area to prevent electrical discharges and surface temperature limits from being exceeded.
Manufacturer Name and Address
The address details for the manufacturing company that was issued the ATEX certificate.
Particles produced by agricultural and chemical industry such as cereal grains, flour, milk powder, pharmaceuticals, animal feed and coal that settle on equipment in layers and form clouds of dust in the air.
The equipment is designed to prevent any electrical discharges form igniting the surrounding hazardous atmosphere.
Notified Body Identification Number
A Notified Body is an organisation appointed by the applicable authority in the European member country to carry out ATEX consultation, assessment and certification of organisations and products. In the UK for example the authority would be the Health and Safety Executive. Each Notified Body is issued with a unique identification number by the EU member state authority.
Oil Filled (o)
The equipment is completely immersed in oil to prevent the transmission of any ignition source to a flammable gas external to the equipment.
Powder Filled (q)
The equipment is completely covered in a powder which will prevent the transmission of any potential source that might ignite an explosive gas atmosphere.
The equipment is continously purged of flammable gases and flammable dust or gas is prevented from entering by supplying a non-flammable gas such as Air at a positive pressure.
The part number and description issued by the manufacturer for the ATEX approved product. The product ID should also correlate with the one which appears on the ATEX certificate.
Restricted Breathing (nR)
Equipment is placed inside an enclosure which limits flammable gases entering to very low level.
The maximum safe temperature permitted on the surface of the product to prevent ignition of surrounding combustible dust.
Surface Temperature with Dust Layer
The maximum safe temperature allowed to prevent ignition of dust that has settled on the product. The thicker the dust layer the lower the required surface temperature due to its increased heat capacity. The thickness of dust is specified in millimetres (mm).
A unique number issued by the manufacturer to identify an individual product.
The permittable range of surrounding ambient environment temperature to ensure the maximum allowable surface temperature for the product is not exceeded.
Maximum surface temperature of product must not exceed this temperature:
- T1 – +450 degC
- T2 – +300 degC
- T3 – +200 degC
- T4 – +135 degC
- T5 – +100 degC
- T6 – +85 degC
Specifies the level of safety risk for restricted areas with explosive Gas (G) or Dust (D) atmospheres:
- Gas Zone 0 – Explosive atmosphere is present at all times, for extended periods or often.
- Gas Zone 1 – Explosive atmosphere is likely to be present during typical operation or occasionally.
- Gas Zone 2 – Explosive atmosphere maybe present during exceptional conditions for a short period of time.
- Dust Zone 20 – Explosive atmosphere is present all the time, for long period of time or often.
- Dust Zone 21 – Explosive atmosphere is likely to be present under normal operation or occasionally.
- Dust Zone 22 – Explosive atmosphere maybe present under exceptional conditions for a short period of time.
The year in which the product that is marked was manufactured.