7 steps to choosing the safest pressure transmitter for hazardous areas

When selecting an ATEX or IECEx certifiedpressure transmitter , it is important to consider the specific industrial group that applies to your installation. This will enable you to choose a pressure transmitter adapted to the specific hazards present in your environment. By taking these precautions, you can help ensure the safety of your employees and equipment.

The pressure transmitters we offer are specifically designed to meet the needs of hazardous areas. We offer two different types, depending on the type of area you need them for: surface industry or mining.

According to the ATEX or IECEx directives, explosive atmospheres are classified as either Zone 0, 1 or 2. Zone 0 is classified as a permanent risk, while Zone 1 is classified as an occasional risk. Zone 2 is classified as a risk. For each zone, there are different types of pressure transmitters suitable for use in explosive atmospheres. For example, in zone 0, only explosion-proof or intrinsically safe pressure transmitters can be used. In Zone 1, dust-ignition-proofpressure transmitters can be used. And in Zone 2, any type of pressure transmitter can be used.

When selecting a pressure transmitter for use in an explosive atmosphere, it is important to take into account the sensor class and the area in which it will be used. The wrong sensor could result in a devastating explosion.

There are two main types of flammable substance: gas and dust. Gas is easier to detect, as it is more visible, while dust can be more difficult to identify. Both types of flammable substances can be explosive, so it's important to choose a pressure transmitter suitable for working in explosive areas.

Select gas/dust sensors according to the type(s) of chemicals that may circulate in the area, as well as potentially volatile liquids such as certain fuels.

There are two types of ATEX or IECEx certified pressure transmitters :

• Those marked " Ex ia " are intended for use in zone 0, where concentrations of flammable gases or vapors are continuously high.
• Ex d" pressure transmitters , on the other hand, are designed for use in Zone 1, where flammable gases or vapors are only occasionally present.

To ensure safety, it's important to choose the right protection mode for your specific needs. This means choosing a precise device, such as sensors with different technologies depending on where they are to be installed: piezoresistive, capacitive.

To avoid accidental ignition, you need to choose a pressure transmitter suitable for the type of gas you're using. The risk of gas ignition is classified into three categories: flammable, combustible and inert.

• Flammable gases, such as hydrogen, can ignite even at very low concentrations.
• Combustible gases, such as methane, require a higher concentration to ignite, but remain potentially dangerous.
• Inert gases, such as nitrogen, are not flammable and can be used safely in potentially explosive areas.

By choosing a pressure transmitter classified in the right ignition risk class, you can help prevent accidental fires and explosions.

Depending on the application, the sensor must be able to withstand different levels of dust exposure. For example, in a coal mine, the dust is relatively large and not very conductive. In a flour mill, on the other hand, the dust is smaller and more conductive. The type of pressure transmitter you choose must be able to adapt to the size and conductivity of the dust. If the sensor is not dust-compatible, it may fail prematurely, or even explode. You therefore need to match the size and conductivity of the dust to the type of pressure transmitter you choose.

It is important to choose a sensor with an appropriate surface temperature range. This will ensure that the sensor can withstand the temperatures present in the explosive area.
The most common temperature ranges for explosive atmospheres are T1, low temperature, and T2, high temperature. If the sensor is not specified for the correct temperature range, it may not be able to provide accurate readings, or may even fail.
Choosing the right sensor with the appropriate surface temperature range is essential to ensure safe and accurate operation in an explosive environment.

In addition to the ATEX or IECEx designation, you should also check the protection rating of the pressure transmitter. This will give you an indication of how well the device is protected against the ingress of foreign bodies and liquids, both of which can cause a fire or explosion. By choosing a pressure transmitter with the appropriate safety ratings, you can help ensure a safe and productive working environment.

When choosing an industrialpressure transmitter for a potentially explosive area, it's important to consider the ATEX or IECEx marking.

ATEX certification is a fundamental provision of the European Directive on Explosive ATmospheres Directive 2014/34/EU. IECEx certification is the international certification system supported by the IEC International Electrotechnical Commision. ATEX standards therefore apply to Europe, while IECex standards apply to the rest of the world. These coding rules provide invaluable information for verifying the sensor's conformity to operating conditions.