Intrinsically Safe Barriers

Shop intrinsically safe barriers engineered to limit voltage and current to levels low enough that they cannot ignite flammable gases, vapors, or combustible dust in classified hazardous areas. Certified Zener diode and galvanic isolation barriers sit between field instrumentation in Zone 0, Zone 1, or Zone 2 locations and control equipment in a safe area, restricting the energy that reaches sensors, transmitters, and switches even under fault conditions. Our selection covers single-channel and multi-channel barriers for common signal types, including 4-20mA loops, digital switches, thermocouples, and RTDs, so instrumentation engineers can protect existing control systems without redesigning the entire measurement loop. Because barrier selection depends on the specific hazardous area classification, the connected instrument’s entity parameters, and loop voltage and current limits, our specialists can help confirm the correct barrier model and wiring configuration for your installation before you order. Properly specified intrinsically safe barriers keep process instrumentation compliant with ATEX, IECEx, and North American Class/Division requirements while protecting personnel and equipment from ignition risk. Common applications include oil and gas production and refining, chemical and petrochemical processing, offshore platforms, and pharmaceutical manufacturing, anywhere continuous process monitoring must continue safely inside a classified Zone 0, 1, or 2 area. Browse our certified barrier options below, filter by channel count and signal type, and contact our team for help matching a barrier to your loop.

High-Performance Intrinsically Safe Barriers for Hazardous Locations

Intrinsically Safe (IS) Barriers are essential safety devices that protect personnel and equipment in hazardous environments. They function as energy-limiting interfaces installed between control systems in a safe area and field instrumentation located in a hazardous area. By regulating the voltage and current sent to field devices, IS barriers ensure the energy level remains below the threshold required to ignite a specific flammable atmosphere, effectively preventing fires and explosions. Our curated selection of IS barriers provides the highest level of protection for your critical safety instrumented systems.

Types of Intrinsically Safe Barriers: Zener vs. Galvanic

Choosing the correct type of barrier is critical for system integrity and safety. We offer two primary types of intrinsically safe interfaces, each with distinct advantages for different applications.

Zener Diode Barriers

Zener barriers are passive devices that use Zener diodes, resistors, and fuses to divert excess electrical energy to a dedicated, high-integrity earth ground. They are a cost-effective and reliable solution for many applications. Key characteristics include:

  • Simple, passive circuit design for high reliability.
  • Compact form factor, allowing for high-density mounting.
  • Requires a dedicated intrinsically safe earth ground connection (typically less than 1 ohm).
  • Lower upfront cost compared to galvanic isolators.

Galvanic Isolators

Galvanic isolators provide full electrical isolation between the hazardous and non-hazardous area circuits using components like transformers, opto-couplers, or relays. This isolation eliminates the need for a specialized earth ground, simplifying installation and preventing issues related to ground loops. Key advantages include:

  • No requirement for a high-integrity IS earth ground.
  • Immunity to ground loop noise and interference.
  • Often include signal amplification and conversion features.
  • Can be used for a wider range of signals, including thermocouples and RTDs.

Key Certifications for IS Barriers

Compliance with international safety standards is non-negotiable. The barriers in our catalog are certified by leading global bodies to ensure they meet stringent safety requirements for use in classified locations. When selecting a barrier, it is crucial to match its certification with the specific hazardous environment of your application.

  • ATEX: A mandatory certification for all equipment intended for use in potentially explosive atmospheres within the European Union.
  • IECEx: An international certification system that provides a globally recognized standard for equipment used in hazardous locations, facilitating international trade and ensuring a high level of safety.
  • UL/cUL: Certifications from Underwriters Laboratories for the United States and Canada, respectively, indicating that a product meets North American safety and performance standards for hazardous environments (Divisions or Zones).

Applications and Industries

Intrinsically safe barriers are a cornerstone of safety in industries where flammable gases, vapors, or combustible dusts are present. They are used to protect a wide array of field devices, ensuring that signals can be transmitted safely into and out of hazardous areas. Common applications include:

  • Oil & Gas: Protecting sensors, transmitters, and valve positioners on drilling rigs, refineries, and pipelines.
  • Chemical Processing: Safeguarding control loops for reactors, mixers, and storage tanks.
  • Pharmaceuticals: Ensuring safety in solvent-rich environments during manufacturing and processing.
  • Mining: Preventing ignition sources in environments with methane gas or coal dust.
  • Food & Beverage: Mitigating risks in facilities with combustible dust from grains, sugar, or flour.

Find the Right IS Barrier for Your System

Protecting your operations starts with selecting the correct components. Browse our comprehensive collection of Zener barriers and galvanic isolators above. Consider your specific needs, including loop voltage, signal type, channel count, and the required hazardous area certifications. If you need assistance, our team of experts is ready to help you navigate the complexities of intrinsic safety. Contact us today for technical support or a custom quote to ensure your facility operates with the highest degree of safety and reliability.

Frequently Asked Questions About Intrinsically Safe Barriers