What are the 3 classes of hazardous locations?

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 hazardous area classifications?

Those areas where the possibility or risk of fire or explosion might occur due to an explosive atmosphere and/or mixture is often called a hazardous (or classified) location/area. Currently there are two systems used to classify these hazardous areas; the Class/Division system and the Zone system.

How do you classify ATEX zones?

ATEX zones are classified according to two parameters: – the types of combustibles that may be encountered (dust or gas) – the frequency or duration during which an explosive atmosphere is likely to occur. Carefully read the Instructions for Use used in this technical advice before consulting the advice itself.

What are the applicable zones for explosive dust atmospheres?

Zones 20, 21 & 22: Hazardous Areas due to the presence of combustible dusts, fibres or flyings (AS/NZS/IEC 60079-31)

What is Zone 2 area classification?

The definition of Zone 2 is a hazardous area classified as an atmosphere where a mixture of air and flammable substances in the form of gas, vapour or mist is not likely to occur in normal operation, but if it does occur, will persist for a short period only.

What is a Class 1 Division 2 area?

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 is a zone 22 area?

Zone 22 A place in which an explosive atmosphere in the form of a cloud of combustible dust in air is not likely to occur in normal operation but, if it does occur, will persist for a short period only.

How many zones are there in hazardous area classification?

This level of risk is represented by classifying the hazardous area as Zone 0, Zone 1 or Zone 2 (for gas, vapour and mist atmospheres) or Zone 21 or Zone 22 for dust atmospheres.

What does Zone 21 mean?

A Zone 21 area is classified as a place in which an explosive atmosphere consisting of a mixture with air or flammable substances in the form of powder or dust is likely to occur in normal operation occasionally. These are typically process areas where dusts and powders are more likely to be present.

What is hazardous area classification schedule?

Hazardous area classification drawing outlines the classifications of areas where flammable liquids, gasses or vapors are handed, processed or stored. It is created based on input from the Process Flow Diagrams, Piping & Instrumentation Diagrams and the Equipment Location Plan.

What is a Class 1 Division 1 area?

A Class I, Division 1 area encompasses the combination of Zone 0 and Zone 1 areas. An area where ignitable concentrations of flammable gases, vapors or liquids are present continuously or for long periods of time under normal operating conditions.

What is the purpose of hazardous area classification?

Hazardous area classification is: a method of analysing and classifying an area to facilitate appropriate equipment selection. key to reducing the risk of fires or explosions and keeping dangerous work environments safe. critical in protecting people, plant and equipment.

What is the 5 types of hazard?

The aim of this guide is to help you understand the different categories of hazards, so you can confidently identify them in your workplace.
  • Biological Hazards.
  • Chemical Hazards.
  • Physical Hazards.
  • Safety Hazards.
  • Ergonomic Hazards.
  • Psychosocial Hazards.

Does Class 1 Div 2 require explosion proof?

A Class I Division 2 light are not held to as high of a standard as Division 1 products. To meet the requirements for Division 2, a light does not have to be able to contain an explosion. Instead, they must be found to be unable to cause an explosion in environments for which they are approved to be used.

What is a Class 2 Division 1 hazardous location?

Division 1 is a subset of Class II and is classified as an area where the explosive or flammable combustible dusts mentioned above can exist under normal, everyday operating conditions.

What is the difference between Zone 1 and Zone 2?

Zone 1: An area in which an explosive gas atmosphere is likely to occur in normal operation; Zone 2: An area in which an explosive gas atmosphere is not likely to occur in normal operation and, if it occurs, will only exist for a short time.

What is a Class 2 Division 2?

Class 2 Division 2, also commonly written with a Roman numeral “Class ii Division 2”, represents an area where combustible dust may be present in quantities sufficient to ignite or explode.

What are the requirements for Class 1 Div 2?

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.