Why You Need Hazardous Area Rated Humidity & Temperature Instrumentation

ATEX-rated products, designed to operate safely in explosive atmospheres, are critical to ensure safety across various industries. The term "ATEX" originates from the French "Atmosphères Explosibles," and represents a comprehensive framework within the European Union (EU), aimed at safeguarding equipment and systems used in potentially explosive environments. These standards and directives are instrumental in preventing accidents, protecting human lives, and preserving valuable assets. Similar standards apply globally, including IECEx, NEC and CEC.

The Rotronic hazardous area rated equipment range (HygroFlex5-EX), used in conjunction with the hazardous area rated digital probe range (HC2-EX, is engineered explicitly for precise measurements of humidity and temperature in explosive atmospheres. The importance of measuring relative humidity and temperature in such environments relates to product quality, safety, process efficiency and compliance. PST has a long history of working with instrumentation in hazardous areas, from Oil and Gas to Additive Manufacturing. We are proud of our deep knowledge in the areas of certification, SIL and hazardous area products. In this blog, we look closer at some potentially explosive applications where humidity and temperature in particular play a pivotal role:

1. Grain and Flour Monitoring

One crucial application of hazardous area rated humidity and temperature measurement equipment is in flour and grain silos and pneumatic conveying systems that transport flour within large factories and mills. Flour, being a finely ground substance, is susceptible to forming explosive dust clouds when suspended in the air. Monitoring relative humidity and temperature within flour and grain industry is essential for several reasons:

• Dust Explosion Prevention: Flour and grain dust is highly combustible, and the presence of an explosive dust cloud in a confined space poses a severe explosion hazard. ATEX-rated measurement instruments have a twofold impact on potential risks. Firstly, by accurately maintaining humidity levels within a safe range, the risk of dust becoming airborne is reduced. At the same time, using hazardous area certified devices ensure that, even in the event of dust build-up leading to a potentially explosive atmosphere, no spark or ignition source can be created by the instrumentation.
• Worker Safety: The safety of workers handling flour and working near silos is paramount. ATEX-rated measurement equipment helps create a safe working environment by minimizing the risk of dust explosions, which can endanger the lives of employees.
• Product Quality: Flour and grains are highly susceptible to environmental conditions. Physically, high humidity can lead to clumping in powders affecting distribution systems and packaging. Extreme temperature fluctuations can cause condensation inside the silo. If humidity levels are too high, spoilage or seed germination can occur. Monitoring these factors ensures that the grains and flour remain of high quality and suitable for use.
• Regulatory Compliance: Compliance with safety regulations is mandatory in many regions. Using hazardous area rated equipment helps companies adhere to these regulations, thereby avoiding legal penalties and ensuring the safety of workers and facilities.
• Operational Efficiency: Proper measurement and control of humidity and temperature can enhance the flow properties of these products and reduce unnecessary heating and drying, reducing the risk of blockages and improving overall operational efficiency in material handling and storage.

2. Explosive Manufacturing and Storage

ATEX-rated humidity and temperature measurement equipment is also instrumental in explosive manufacturing and storage facilities. The following points highlight their significance:

• Preventing Unintentional Detonation: Explosive materials are highly sensitive to environmental conditions. Maintaining precise temperature and humidity levels is critical to prevent unintentional detonations or the degradation of explosive compounds. In particular, high humidity can induce instability in some explosive mixtures, while extreme temperatures can alter their sensitivity. Humidity is often used to prevent static build-up that can be the source of ignition or directly damage electrical components.

3. Ammunition and Ordnance Storage

Military and law enforcement agencies rely on ATEX-rated measurement equipment to ensure the safety and integrity of ammunition and ordnance storage facilities:

• Corrosion Prevention: Monitoring humidity and temperature helps prevent moisture-related corrosion of ammunition casings and components, ensuring that these items remain reliable and safe for use. Military and aerospace equipment can often be in storage long term, and any ammunition and fuel kept close by requires accurate monitoring and control of humidity with instruments that do not impose ignition sources.

4. Mining and Demolition

Explosives are indispensable in mining and demolition operations, where safety is paramount:

• Stability Assurance: Explosives used in such operations must be stored and handled under specific environmental conditions to guarantee their stability and reliability. Accurate humidity control is necessary to avoid unpredictable results, while temperature management helps maintain the stability of these explosives.

5. Oil and Gas Industry

Many oil and gas facilities are considered explosive atmospheres due to the presence of flammable gases or dust. ATEX-rated measurement and analyzing instruments are ubiquitous in these applications and play a critical role in safeguarding personnel and equipment:

• Preventing Explosive Mixtures: Monitoring temperature and humidity is crucial in hazardous areas to prevent the formation of explosive mixtures, reducing the risk of catastrophic incidents.

6. Pyrotechnics and Fireworks

In firework displays, pyrotechnics and fireworks rely on precise timing and ignition:

• Effect Optimization: Relative humidity affects the burn rate and trajectory of pyrotechnic devices. Accurate humidity and temperature measurements are essential for achieving desired visual effects and ensuring the safety of these spectacular displays.

In summary, ATEX-rated or hazardous area products, such as the HygroFlex5-EX and HC2-EX probes, are integral to ensuring safety and compliance with regulations in many applications where explosive atmospheres are a potential hazard. Their role extends beyond safety to quality, maintenance, operational efficiency and asset protection. By safely monitoring and helping control humidity and temperature, these products contribute significantly to minimizing the risk of accidents, maintaining product integrity, and upholding stringent regulatory and safety standards in various industries.

Related Content

• Choose the Right Humidity Transmitter for Your Application
• Understanding ATEX and IECEx