Hazardous Area Fire and Safety with LLIS Liquid Level Switches

Intrinsically Safe Monitoring of Hydrocarbons, Fuels, and Flammable Liquids

In industries where hydrocarbons, fuels, and other flammable liquids are stored, transferred, or processed, reliable liquid level detection is essential for safety and regulatory compliance. Even minor leaks or overfills can pose fire, explosion, and environmental hazards.

Industry Challenges

Engineers and operators working in hazardous areas encounter multiple challenges:

• Explosion Risk – Electrical equipment must not generate sparks or arcs that could ignite vapors or flammable liquids.
• Certification Requirements – Sensors must comply with ATEX, IECEx, or equivalent approvals for use in explosive atmospheres.
• Chemical Resistance – Direct contact with fuels, oils, solvents, and other chemicals requires durable sensing materials.
• Continuous Reliability – Safety-critical systems demand sensors that perform consistently to prevent spills, leaks, or accidents.
• Maintenance Limitations – Devices must minimize servicing in hazardous zones to reduce downtime and operator exposure.

Solution Overview – SST LLIS Hazardous Area Approved Liquid Level Switch

The  SST LLIS – Hazardous Area Approved Liquid Level Switch is engineered and certified to operate in these demanding environments. Combining robust construction with intrinsic safety, it provides dependable performance where conventional sensors may fail. The LLIS switch is specifically designed for hazardous zones, delivering accurate and continuous liquid level monitoring in critical safety applications.

Key Features & Benefits

• Intrinsic Safety – Designed to prevent sparks, arcs, or thermal effects that could ignite flammable liquids or vapors.
• Hazardous Area Certification – ATEX and IECEx approvals ensure safe deployment in explosive atmospheres.
• Robust Construction – Resistant to hydrocarbons, fuels, and aggressive chemicals for long-term durability.

SST offers multiple housing materials to meet the demands of specific environments. Polysulfone is used for its combination of high mechanical strength, chemical resistance, temperature stability, and excellent electrical properties, making it ideal for applications where durability and reliability are important. Grilamid is selected for environments involving gasoline, petrol, and diesel due to its resistance to harsh chemicals, temperature fluctuations, and pressure variations. Trogamid is particularly suited to applications where chemical resistance is critical, such as in the food and beverage industry, as it performs reliably with a wide range of liquids, including oil- or water-based substances.

O-ring options further enhance the sensor’s reliability. Viton is recommended for high-temperature, high-pressure, and strong chemical environments, while Nitron is optimized for fuels, oils, and coolants.

Compact, Reliable Design – Simple installation with no moving parts, reducing failure points and maintenance needs.

Critical Safety Assurance – Detects leaks, overfills, or low-level conditions to protect personnel and equipment.

Proven Performance – Extensively tested for reliable operation in oil & gas, petrochemical, and industrial environments.

Applications & Industries

The LLIS liquid level switch is widely deployed in industries where hazardous environments are common:

• Oil & Gas – storage tanks, pipelines, and offshore platforms
• Petrochemical plants
• Fuel storage and distribution facilities
• Aviation fueling systems
• Chemical manufacturing and processing
• Leak detection in hazardous process environments

Conclusion

In hazardous areas, intrinsic safety is essential for protecting personnel, equipment, and operations. The SST LLIS Hazardous Area Approved Liquid Level Switch delivers reliable, certified monitoring in environments exposed to hydrocarbons, fuels, and other flammable liquids. With robust construction, globally recognized approvals, and housing and O-ring materials tailored for chemical and temperature resilience, it ensures consistent performance in safety-critical applications. Trusted by engineers and safety professionals worldwide, the LLIS switch is the preferred solution for hazardous area monitoring, providing peace of mind where safety cannot be compromised.