what is explosion proof classification

What Is Explosion Proof Classification

• Explosion-Proof Classes There are three classes of hazardous areas that define the type of flammable substances present in the environment. ...
• Divisions Hazardous locations are classified based on the probability of high concentrations of the dangerous substance being present under working circumstances–enough to react in combustion. ...
• Groups ...

Full Answer

What are the classes of explosion proof locations?

Explosion Proof Classifications Class Definitions Class I Locations: Are those in which flammable gases or vapors are or may be present in the air in quantities sufficient to produce explosive or ignitable mixtures. Class II Locations: Are those which are hazardous due to the presence of combustible dust. Class III

What does explosion-proof classification mean?

Industrial facilities also utilize divisions such as Explosion-Proof classification to denote the required safety within a hazardous environment. Understanding how to read Explosion-Proof classification will allow you to accurately assess your safety circumstances and comply with the safety regulations of your worksite.

What is the class component of an explosion zone classification?

The class component of an explosion zone classification system determines the properties of hazardous materials present in any given environment. Hazardous materials are categorized into three main groups: Class I environments where hazards are flammable vapors and gases present in sufficient quantities to form explosive mixtures

What is an explosion-proof sensor?

An explosion-proof classification for a sensor/transmitter means that the housing has been designed to contain a flash or explosion. The housings are usually made of cast aluminum. What is explosion-proof wiring? conduits and seals are required for explosion proof wiring. These are to make sure the circuit is free of hazardous gases.

Is IP55 explosion proof?

Coming with feet support for stable mounting of motors, these Explosion Proof Mounted Motor choices provide for superior performance and work precision as required in defined applications....Three Phase Explosion Proof Mounted Motor, IP Rating: IP55.BrandCrompton, ABBIP RatingIP55PhaseThree Phase1 more row

Does Class 1 Div 2 require explosion proof motors?

While Division 1 motors in Class I locations must be explosion-proof, Class II, Division 1 motors must be dust- ignition-proof.

What is explosion proof material?

Explosion Proof Materials (Non-sparking) Copper-aluminum alloys, stainless steel, silver, aluminum and galvanized steel are examples of metals that are non-sparking.

What does Class 1 Group D mean?

Hazardous Locations. Class I Group D locations are atmospheres containing elements such as Gasoline, Hexane, Naphtha, Benzine, Butane, Propane, Alcohol, Acetone, Benzol, Lacquer Solvent Vapors or Natural Gas.

How do I know if my motor is explosion proof?

When a spark ignites volatile gas inside a motor, an explosion proof design contains the internal combustion to prevent a greater explosion or fire. An explosion proof motor is clearly marked with a nameplate that identifies its suitability for a given hazardous environment.

What is a Class 1 Div 2 area?

Class I Hazardous Locations refer to facilities which deal with flammable gases, vapors, and liquids. Division 2 specifies that these flammable materials are handled, processed, or used in the defined hazardous location, but are not normally present in concentrations high enough to be ignitable.

What is ATEX explosion proof?

ATEX is an abbreviation for "ATmosphere EXplosible". At the same time, ATEX is the abbreviated name of the European Directive 2014/34/EC concerning the placing on the market of explosion-proof electrical and mechanical equipment, components and protective systems.

What is ATEX certification?

ATEX certification ensures that equipment will work safely in explosive environment without causing any accident if used as per the manufacturer's recommendations. Equipment used in explosive atmosphere within the European Union (EU) and the European Economic Area (EEA) must be ATEX certified.

What is difference between explosion proof and flameproof?

There is no difference except term. Flameproof design is one of the explosion protection technique extensively used for light fittings, JBs, motors in hazardous areas. This is certified by IEC but is predominantly followed in India and is also governed by local IS standards.

What is the difference between Class 1 Division 1 and Division 2?

Class 1 Hazardous Locations refer to facilities that deal with flammable gases, vapors, and liquids. Division 2 specifies that flammable materials are handled, processed, or used at a location. But, concentrations of hazardous substances are not high enough to be ignitable.

What are the 3 classes of hazardous locations?

Let's quickly review. The National Electric Code classifies hazardous locations in three ways: TYPE, CONDITION, and NATURE. There are three types of hazardous conditions: Class I - gas and vapor, Class II dust, and Class III - fibers and flyings.

What are the 3 zone classification?

Zone 0: Explosive atmosphere for more than 1000h/yr. Zone 1: Explosive atmosphere for more than 10, but less than 1000 h/yr. Zone 2: Explosive atmosphere for less than 10h/yr, but still sufficiently likely as to require controls over ignition sources.

Are Tefc motors rated for Class 2 Div 2?

Class II Division 2 However, a TEFC (Totally Enclosed Fan-Cooled) motor can be suitable for Division 2 if it is labeled correctly for Division 2 with the Class and Group, and if it has thermal sensors and proper t-code temperature ratings.

Which of the following is approved for use in most Class One Division One locations?

which of the following is approved for use is most class 1,division 1 location? all sealing compound can b used in all applications.

What is a NEMA 7 enclosure?

NEMA 7 enclosures are designed to contain an internal explosion without causing an external hazard. These enclosures are intended for indoor use in hazardous locations classified as Class I, Division I, Groups A,B,C, or D.

What is hazardous area classification?

Hazardous areas are defined in DSEAR as "any place in which an explosive atmosphere may occur in quantities such as to require special precautions to protect the safety of workers".

How to Comply with an Explosion-proof Area Classification?

Compliance with explosion-proof classifications depends almost entirely on the use of the right apparatus in workspaces. Explosion-proof equipment with components that can prevent the ignition of sparks within a potentially combustible space is highly recommended.

What is the class component of an explosion zone classification system?

The class component of an explosion zone classification system determines the properties of hazardous materials present in any given environment. Hazardous materials are categorized into three main groups:

What is intrinsically safe equipment?

Intrinsically safe equipment is defined as an apparatus with circuitry where sparks or other thermal effects, are incapable of igniting an explosive mixture of volatile materials or gases under predetermined test conditions.

What is a hazardous area?

Hazardous classified locations are environments in which there is a potential risk of fire or explosion due to their containment of volatile gases or dust. Hazardous area classifications are a grouping system that recognizes the risk associated with various volatile materials and determines the appropriate protection measures needed ...

What is explosive atmosphere classification?

An explosive atmosphere classification also considers the probability of potentially hazardous material being present in an environment in concentrations enough to cause an ignition. Two main divisions are recognized below: Division 1 substances are classified as high probability materials.

What is class II hazardous?

Class II hazardous materials are combustible dust present in quantities enough to trigger an explosion or ignite a fire. Class III materials are fibers or flying particles present in an environment. These materials may or may not be sufficient to cause an explosion or start a fire.

How many groups are there in hazardous areas?

The hazardous area classification guide for groups divides the type of potentially explosive material contained in an environment into the six groups listed below:

Why explosion proof?

Explosive substances: some combustible substances will be produced in many production sites.

Hazard classification of hazardous places

Places where explosive gas mixtures exist continuously or for a long time under normal conditions.

Classification of explosive dangerous gases

According to the minimum spark energy that may be detonated, China, Europe and most countries and regions in the world classify explosive gases into four hazard levels, as shown in the following table:

Explosion proof signs of instruments

Note: there is no temperature group item in this sign, indicating that the instrument is not in direct contact with explosive gas.

What is explosion proof IP rating?

The International Protection Marking is a component of the classification system for the levels of protection against explosion and fire in electrical enclosures.

Is Class I Div 2 explosion proof?

A Class I Division 2 light is not the same as a Division 1 product. There is no requirement for a light to contain an explosion to meet the requirements for Division 2. They can’t cause an explosion in environments that they’re approved to be used in.

What Is an Explosion-Proof Motor?

There are two scenarios in which an electric motor can cause an explosion:

What are the types of vapors that are known to cause explosions?

Class I — Class I locations contain gases and vapors that are known to auto-ignite and cause explosions. Gasoline and acetylene are common examples of such vapors.

Why are electric motors not explosion proof?

But not all explosion-proof electric motors can handle flammable matter in the same capacity. And simply because a motor operates in a hazardous location, the motor is not necessarily explosion-proof.

What type of motor do you need for a Division 1 explosion?

If you are a Division I, Class I location, you need a proper explosion-proof electric motor . It should be fully capable of confining the effects of an internal explosion, as the slightest exposure to sparks can auto-ignite the flammable vapors in the atmosphere.

What is a hazardous location motor?

By default, all Division I equipment will also serve Division II requirements. Motors that serve Division II locations are generally referred to as hazardous location motors — motors that can handle anomalous hazardous situations.

What is Division 2?

Division II — A Division II location becomes hazardous in abnormal conditions. If there is a rupture, burst, or leak resulting in spillage or seepage of inflammable substances, then the area is considered a Division II property.

Why is it important to know the division, class, and group of your property?

Knowing the division, class, and group of your property is crucial for ensuring you choose a well-suited motor that will improve productivity without introducing the danger of explosions. Likewise, fully understanding the hazardous location and explosion-proof motor standards will greatly reduce the risk of accidents and injuries.

What is a temperature class?

Temperature Classes- Temperature classes relate to a flammable substance and its Auto Ignition Temperature. 100o

What is the responsibility of an employer to protect employees who may be exposed to the risk of explosive atmosphere environments?

The employer must assess the risk and classify potentially dangerous areas. Equipment and materials must also be suited for use in these dangerous areas.

What is a Class I area?

Class I – Created by the presence of flammable gases or vaporsin the air, or flammable liquids, in sufficient quantities to be explosive or ignitable. Class I locations are further categorized by Division (Refer to chart 1) and fall into Group A through D. (Refer to chart 2) Class II – Created by the presence of combustible dust, suspended in the air, in sufficient quantities to be explosive or ignitable. Class II locations are further categorized by Division (Refer to chart 1) and fall into Group E through G. (Refer to chart 3) Class III – Areas where there are easily ignitable fibers or flyingspresent. These include cotton lint, flax, and rayon as examples. The fibers in a Class III area are not likely to be in the air, but can collect around machinery or on lighting fixtures. A Class III location can be categorized as Division 1 or 2. (Refer to chart 1)

What temperature should electrical equipment be tested?

The temperature classification on the electrical equipment label will be one of the following (in degrees Celsius):

What is a hazardous location?

Hazardous locations are those areas where fire or explosion hazards may exist due to the presence of substances that are flammable, combustible, or ignitable. These locations are broken down into Classes and Divisions, and further defined by Groups and Temperature Classifications.

How many directives does ATEX have?

ATEX consists of two European (EU) directives. They are:

Classes

Class is used to provide a general definition of the physical characteristics of the hazardous material with which we are dealing. The Three hazardous location classes are:

Divisions

The division designation signifies the properties of material responsible for the potential hazard with the likelihood of the hazard actually being present.

Groups

Group designations are used to selectively group the material by comparatively similar hazardous characteristics.

Summary

Division: Classifies the likelihood of the presence of the hazardous condition

Methods of Stopping Ignition

Even though dust, liquids, and gases differ a lot from each other in almost all aspects, the one thing that unites them is their trigger point or ignition. If they don’t ignite, there is no issue. So, how does ignition occur?

Classification of Hazardous Locations and Devices

To ensure proper and safe lighting in the areas that remain vulnerable to hazardous accidents, the National Electric Code or NEC has set standards that classify the various risk levels meant for lightings to be approved as HAZLOC safe. This is meant to help you identify the right light for your location if it lies in the hazardous category.

What is explosion proof equipment?

Article 100 defines explosion-proof equipment as “equipment enclosed in a case that is capable of withstanding an explosion of a specified gas or vapor that may occur within it and of preventing the ignition of a specified gas or vapor surrounding the enclosure by sparks, flashes, or explosion of the gas or vapor within, and that operates at such an external temperature that a surrounding flammable atmosphere will not be ignited thereby.”

What could compromise the flanges of explosion proof equipment?

After I cleared that up, I examined the equipment. Right away, I noticed all the equipment flanges were damaged. Many had scratches or scuff marks on them, which could compromise the flanges’ ability to cool escaping gases. Flanges of explosion-proof equipment need to be protected from damage. I also noted that pipe dope had been applied to conduit threads. Pipe dope could limit the ability of burning gas to escape, which could cause the enclosure to rupture. Clearly, this installation was not going to pass inspection. Discarding the equipment would be costly and delay the project.

What is the process of supplying an enclosure with a protective gas with or without continuous flow at sufficient pressure?

Pressurization is defined as the process of supplying an enclosure with a protective gas with or without continuous flow at sufficient pressure to prevent the entrance of a flammable gas or vapor, a combustible dust or an ignitable fiber. Pressurization can be used in both Class I and II locations.

Why do we need explosion tests?

Explosion tests are usually needed to demonstrate the acceptability of the enclosure design. Figure 3 illustrates the need to properly install all provided bolts, screws, fittings and covers. It is very common to find that bolts are missing or mismatched. If bolts are missing, it is essential that the manufacturer’s specified bolts are used for replacement.

What happens when an explosion occurs in an enclosure?

If an explosion occurs within an enclosure or conduit system, the burning mixture or hot gases must be sufficiently confined to prevent the ignition of any explosive mixture that could exist outside of the equipment. To prevent a rupture, which could release burning or hot gases, the enclosure must have sufficient strength to withstand the pressure generated by an internal explosion. During an explosion, gases escape through any paths or openings that exist in the enclosure.

How does an explosion prevent a rupture?

During an explosion, gases escape through any paths or openings that exist in the enclosure.

Why does the clearance between flat surfaces increase under explosion conditions?

The clearance between flat surfaces can increase under explosion conditions because the internal pressures created by the explosion tend to force the surfaces apart (Figure 3).

What Is An Explosion-Proof motor?

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