Safety in the chemical industry: Measurement technology for extreme conditions

The chemical industry is characterised by complex processes in which aggressive chemicals are used, and explosion hazards and challenging conditions frequently arise. Even the smallest errors can have far-reaching consequences – from costly production downtimes to safety risks for humans and the environment. Key aspects of chemical plant safety are explosion protection, functional safety and cybersecurity.

VEGA offers sensors designed to meet these challenges. They measure level and pressure with high precision, even under extreme conditions, and help make processes safe and efficient.

In the hazardous areas of chemical plants, flammable gases or dusts can pose significant risks. The zone concept divides hazardous areas into different zones based on the frequency and duration of explosive atmospheres. Zone 0 (gas atmosphere) or Zone 20 (dust) describes areas where an explosive atmosphere is present continuously or for long periods, such as in tanks containing flammable liquids. Zone 1 or 21 covers areas where explosive atmospheres can occasionally occur under normal operating conditions, for example at plant ventilation ports. Zone 2 or 22 refers to areas where an explosive atmosphere occurs only rarely and only for short periods, such as in the vicinity of pumps. This zone concept is used to determine suitable protective measures and instrument types that may be deployed in the respective areas.

Sensors from VEGA are equipped with protection concepts that help to minimise these hazards:

• Intrinsic safety (Ex i): Sparks and overheating are prevented by limiting electrical energy.
• Flameproof enclosure (Ex d): The housing provides protection by limiting internal explosions and preventing them from escaping.

VEGA sensors meet international standards such as ATEX and IECEx and are suitable for use in zones 0, 1 and 2. High-quality materials like stainless steel and PTFE further increase resistance to aggressive media.

Functional safety aims to reduce risks due to malfunctions in safety-critical applications. In the chemical industry, the standards IEC 61508 and IEC 61511 play a crucial role. They define functional safety as the ability of a safety-related system to minimise risks due to malfunctions in industrial applications and to protect people, the environment and production equipment. It ensures that safety-relevant functions, such as monitoring limit values or shutting down equipment in the event of a fault, are performed reliably. The standard defines safety requirement levels, known as Safety Integrity Levels (SIL), from SIL1 (lowest requirements) to SIL4 (highest requirements). The choice of SIL level depends on the risk assessment and the probability that a fault could lead to a dangerous event. 

IEC 61508 is directed toward equipment manufacturers and covers the entire life cycle of safety-related systems – from development and risk assessment to operation and maintenance – thus providing a systematic basis for ensuring safe processes. IEC 61511 applies the general principles of IEC 61508 and translates them into practical specifications for plant operators in the process industry.

Sensors like VEGAPULS 6X have been developed to fulfil safety requirements up to SIL3. Advanced diagnostic functions detect potential faults at an early stage and switch the sensor to a safe state if necessary. The digital documentation of tests supports plant operators in effectively implementing and monitoring safety standards.

The increased networking of chemical plants, right down to the production area (field), brings with it new challenges: e.g. the possibility of cyberattacks, which can compromise not only data security but also operational reliability.

VEGA pursues a multi-level security concept, which has been realised, for example, in the new radar level transmitter VEGAPULS 6X:

• IEC 62443 certification: the instruments are designed to meet high security standards.
• Encrypted communication: Protects against unauthorised access and data manipulation.
• Event memory and integrity check: Records tampering attempts and checks firmware updates.

VEGA's dedicated security team (PSIRT) ensures that threats are quickly identified and appropriate action is taken.

VEGA offers the “Second Line of Defense” concept for safety-critical applications. This is an additional layer of protection behind the process diaphragm, ensuring measurement even under difficult conditions.

Gas-tight feedthroughs and flameproof enclosures, such as those used for VEGAFLEX or VEGABAR, ensure that external influences do not affect the sensors. This concept reduces the risk of breakdown and supports continuous long-term measurement.

VEGA helps to make processes in the chemical industry safer through innovative measurement technology. Level and pressure sensors are designed for extreme conditions and are an integral part of solutions for explosion protection, functional safety, cybersecurity and safety-critical applications.

The combination of robust materials, modern technologies and advanced protection concepts makes VEGA sensors an important part of secure and efficient production systems.