What's the Difference between an Explosion Proof and ...

What's the Difference between an Explosion Proof and an Intrinsically Safe Gas Detector?

MAM contains other products and information you need, so please check it out.

It only takes a spark to start a fire or cause an explosion, especially when flammable gases or vapours are present under the right conditions. There are industries that operate in these types of hazardous environments where the potential for explosions is extremely high, such as chemical plants, oil refineries, paint shops, cleaning facilities, tanks and loading facilities for flammable gases, liquids and solids. OSHA defines hazardous locations as:

Areas where flammable liquids, gases or vapors or combustible dusts exist in sufficient quantities to produce an explosion or fire. In hazardous locations, specially designed equipment and special installation techniques must be used to protect against the explosive and flammable potential of these substances.

Two types of specially designed equipment for use in hazardous locations are explosion proof and intrinsically safe.

Explosion proof is a protection technology that guarantees the housing or enclosure has been designed and constructed in such a way that it is capable of containing, controlling and venting any possible flash or explosion. Enclosures of this kind are typically made of stainless steel or cast Aluminum and are of an appropriate mass and strength that they will safely contain an explosion if flammable gases or vapours should penetrate the housing and the internal electrical components or wiring should cause an ignition. The amount of power to or from the device is not of concern.

Intrinsically safe is an explosion protection technique that ensures that the electrical circuit and its wiring is engineered in such a way that it is not capable of releasing enough energy, or producing a high enough temperature under any condition and thus is not able to cause an ignition of itself or the surrounding area. This specifically designed equipment does not require a special enclosure or housing. Instead, the amount of power the device has is typically controlled through the use of intrinsic safety barriers and as a result, this type of equipment can be used only for very low power applications.

Gas detectors for hazardous location applications must meet strict codes and standards and can be built as either explosion proof or intrinsically safe. Intrinsically safe gas detectors are very common in Europe and explosion proof is the more commonly used method in North America for fixed gas detection systems. With the rugged housing to withstand harsh environments and no limits on the types of sensors, the explosion proof gas detector can be used in a wider range of applications and in particular, for applications that require high power.

Explosion Proof Gas Detector

Intrinsically Safe Gas Detector

Protection Method

Contains and controls the explosion, does not prevent an internal explosion

Prevents an explosion, does not contain an explosion

Enclosure

Stainless steel or cast Aluminum

Standard

Size, Weight

Large, heavy, often bulky

Compact, light

Power Requirements

Power is not controlled, operates at normal power levels

Power is controlled, operates on low power levels

Installation

Want more information on supplier explosion proof? Feel free to contact us.

Difficult: heavy, bulky, requires heavy conduit and seals

Easy: small and does not require expensive accessories

Maintenance & Calibration

Non-intrusive calibration may be done without disconnecting power. Power must be disconnected if opening the device.

Non-intrusive calibration may be done without disconnecting power. Power must be disconnected if opening the device.

Types of Sensors

Electrochemical, infrared, combustible /catalytic or PIDs

Electrochemical (low current sensors only)

Application Examples

                                    Oil Refineries, Drilling rigs on oil fields, Municipal Treatment Plants,                                    Chemical Storage Rooms, Loading facilities for flammable gases, liquids and solids

References
Allen-Bradley, Rockwell Automation (October ) Class/Division Hazardous Location. Retrieved from http://literature.rockwellautomation.com/idc/groups/literature/documents/wp/800-wp003_-en-p.pdf
Bob Svacina and Brad Larson, Turck Inc. (April ). Understanding Hazardous Area Sensing. Retrieved from http://www.parrinst.com/wp-content/uploads/downloads//06/Svacina-Larson_Understanding-Hazardous-Area-Sensing_Intrinsic-Safety.pdf
CorDEX Instruments Ltd. (). Intrinsically Safe or Explosion Proof? Understanding the technology. Retrieved from http://www.transcat.com/media/pdf/cordex-is-explosion-proof.pdf
RKI Instruments, Inc. (February 19, ). What&#;s the Difference Between &#;Explosion Proof&#; & &#;Intrinsically Safe&#;. Retrieved from http://www.rkiinstruments.com/pdf/FAQ_Explosion_Proof.pdf

Safety standards help protect assets and also foster a safe workplace. In potentially hazardous environments, equipment must follow particularly strict standards to reduce the risk of an explosion. Here we explain the difference between equipment labeled as intrinsically safe vs. explosion-proof.

What Does it Mean to be Intrinsically Safe or Explosion Proof? 

The terms intrinsically safe and explosion proof may sound similar, but they are very different. Intrinsically safe means that the piece of equipment itself can&#;t cause an explosion. Meanwhile, explosion-proof means that if an explosion did happen, the device would be protected by an explosion-proof enclosure that helps contain explosions and prevent them from spreading. Therefore intrinsically safe refers to explosion prevention, whereas explosion-proof refers to containment. Depending on your industry and working environment, you may need to use one over the other.

Intrinsically safe equipment cuts off thermal or electrical energy once the temperature gets too high in order to stop hazardous areas from catching on fire. These devices are engineered to limit heat generation and avoid causing an ignition due to elevated voltage and current levels. 

For example, intrinsically safe devices will have simplified circuitry, controlled internal temperatures, and high dust resistance to make it impossible for the device to catch fire. These devices are built so they physically can&#;t trigger combustion when used in an a hazardous environment. As a result, intrinsically safe devices are often lighter weight and less bulky than explosion-proof devices. They can also be more easily maintained without shutting down production.

In contrast, explosion-proof devices don&#;t have to be innately incapable of igniting in a hazardous environment. Instead, explosion-proof devices are housed in an enclosure that can effectively contain an explosion. If the device inside the enclosure does explode, the flames and gases cannot escape and spread to other areas of the facility. These devices are heavier, bulkier, and more time-consuming to install, making them better suited to permanent installations.

How to Choose Intrinsically Safe vs. Explosion Proof Devices

When an electrical appliance is installed in a hazardous area, it&#;s more prone to damage by flammable or combustible gases. And there&#;s a high risk of fires spreading quickly after an initial ignition, which can lead to catastrophic consequences. To minimize these risks, organizations have to use equipment certified as intrinsically safe and/or explosion-proof to prevent combustion and quickly contain fires before they spread.

The type of device you choose (intrinsically safe vs. explosion-proof) will depend on your application&#;s unique requirements. You should work with a certified expert like those at Pruftechnik to determine the best solution for each scenario. However, many facilities find that explosion-proof equipment is best-suited for permanent installations that demand high voltage and power. Meanwhile, intrinsically safe devices might be used for both permanent installations and virtually all portable instrumentation.

What is the Difference Between Flameproof and Explosion Proof? 

Flameproof is another protection technique that leverages enclosures for containment. Flameproof devices are placed into enclosures and sealed shut to keep high pressure from escaping the container and debris from spreading outside the conduits. So, any parts that did ignite would no longer trigger an explosive reaction in the surroundings. 

Flameproof and explosion-proof techniques overlap on the scale of embedded safety, available tools, and underlying process. The key differences between them are found in the specification procedures and testing parameters. Each carries its own regulatory compliance specifications.

Conclusion

Fires and explosions are a risk in many industries, and proper mitigation is key to protecting worker safety, ensuring compliance with the relevant governing bodies, avoiding catastrophic failures, and preventing costly unplanned downtime and operational disruptions. Having the appropriate protective measures &#; including both intrinsically safe and explosion-proof equipment &#; allows engineers and technicians to implement safety controls before accidents can happen.

If you&#;re interested in learning more, speak with one of our specialists. For decades, we&#;ve offered a range of cutting-edge products certified for use in hazardous environments.

The company is the world’s best explosion proof light fixtures supplier. We are your one-stop shop for all needs. Our staff are highly-specialized and will help you find the product you need.