NCCER Electrical Level 3 Module 4
'Hazardous Locations' Questions and
Answers | Latest Version | 2024/2025 |
Correct & Verified
What is a hazardous location in electrical work?
✔✔ A place where there is a risk of fire or explosion due to flammable gases, vapors, or dust.
Why is it important to classify hazardous locations?
✔✔ To ensure the right electrical equipment is used to prevent ignition sources in dangerous
environments.
What type of areas are considered Class I hazardous locations?
✔✔ Areas where flammable gases or vapors may be present in the air in quantities sufficient to
create an explosion hazard.
What is a Class II hazardous location?
✔✔ A location where combustible dust may be present in the air, creating an explosion or fire
hazard.
1
,What is a Class III hazardous location?
✔✔ A location where easily ignitable fibers or flyings are present in the air, posing a fire hazard.
What is the purpose of explosion-proof enclosures?
✔✔ To prevent sparks from escaping and igniting hazardous materials in explosive
environments.
Why should electrical equipment used in hazardous locations be properly rated?
✔✔ To prevent electrical sparks, overheating, or arcs that could trigger an explosion or fire.
What is a “Division” in hazardous location classification?
✔✔ A Division indicates the level of likelihood that a hazardous material will be present in a
location.
What does Division 1 mean in hazardous locations?
✔✔ It refers to areas where hazardous materials are likely to be present under normal operating
conditions.
2
, What does Division 2 mean in hazardous locations?
✔✔ It refers to areas where hazardous materials are not likely to be present under normal
operating conditions, but may be present in certain conditions.
What is a Class I, Division 1 location?
✔✔ A location where flammable gases or vapors are present continuously or frequently during
normal operations.
What is a Class I, Division 2 location?
✔✔ A location where flammable gases or vapors are unlikely to be present during normal
operations but could occur under abnormal conditions.
Why is temperature rating important in hazardous locations?
✔✔ Electrical equipment must not exceed a temperature that could ignite hazardous materials in
the area.
What is the function of a purged and pressurized enclosure?
✔✔ It keeps hazardous materials away from electrical components by using a pressurized
environment inside the enclosure.
3
'Hazardous Locations' Questions and
Answers | Latest Version | 2024/2025 |
Correct & Verified
What is a hazardous location in electrical work?
✔✔ A place where there is a risk of fire or explosion due to flammable gases, vapors, or dust.
Why is it important to classify hazardous locations?
✔✔ To ensure the right electrical equipment is used to prevent ignition sources in dangerous
environments.
What type of areas are considered Class I hazardous locations?
✔✔ Areas where flammable gases or vapors may be present in the air in quantities sufficient to
create an explosion hazard.
What is a Class II hazardous location?
✔✔ A location where combustible dust may be present in the air, creating an explosion or fire
hazard.
1
,What is a Class III hazardous location?
✔✔ A location where easily ignitable fibers or flyings are present in the air, posing a fire hazard.
What is the purpose of explosion-proof enclosures?
✔✔ To prevent sparks from escaping and igniting hazardous materials in explosive
environments.
Why should electrical equipment used in hazardous locations be properly rated?
✔✔ To prevent electrical sparks, overheating, or arcs that could trigger an explosion or fire.
What is a “Division” in hazardous location classification?
✔✔ A Division indicates the level of likelihood that a hazardous material will be present in a
location.
What does Division 1 mean in hazardous locations?
✔✔ It refers to areas where hazardous materials are likely to be present under normal operating
conditions.
2
, What does Division 2 mean in hazardous locations?
✔✔ It refers to areas where hazardous materials are not likely to be present under normal
operating conditions, but may be present in certain conditions.
What is a Class I, Division 1 location?
✔✔ A location where flammable gases or vapors are present continuously or frequently during
normal operations.
What is a Class I, Division 2 location?
✔✔ A location where flammable gases or vapors are unlikely to be present during normal
operations but could occur under abnormal conditions.
Why is temperature rating important in hazardous locations?
✔✔ Electrical equipment must not exceed a temperature that could ignite hazardous materials in
the area.
What is the function of a purged and pressurized enclosure?
✔✔ It keeps hazardous materials away from electrical components by using a pressurized
environment inside the enclosure.
3
