Print this page NFPA Standard for Purged and Pressurized Enclosures for Electrical Equipment
Course Outline
This 5-hour course provides for the study of the requirements for purging and pressurizing enclosures to prevent ignition of a flammable atmosphere. Such an atmosphere may be introduced into the enclosure by a surrounding external atmosphere or by an internal source. By these means, electrical equipment that is not otherwise acceptable for a flammable atmosphere may be utilized in accordance with Article 500 or Article 505 of NFPA 70.
The course materials are based entirely on the NFPA 496, Standard for Purged and Pressurized Enclosures for Electrical Equipment, 2017 Edition.
This course includes
a multiple-choice quiz at the end, which is designed to enhance the understanding
of the course materials.
Learning Objective
At the conclusion of this course, the student will be familiar with:
- Definitions of the terms that are used in this standard;
- The general requirements for pressurized enclosures;
- The requirements for a pressurizing system;
- Type Z pressuring;
- Type Y pressurizing;
- Type X pressurizing;
- The requirements for pressurized enclosures in Class I locations;
- The requirements for pressurized enclosures in Class II locations;
- The requirements for pressurized control rooms;
- The requirements for pressurized enclosures having an internal source of flammable gas or vapor;
- The requirements for pressurized analyzer rooms containing a source of flammable gas, vapor, or liquid;
- Typical alarm and indicator configurations for Types Y and Z pressurizing;
- The requirements for the protective gas system;
- Determining the temperature marking; and
- The additional marking requirements for protected enclosures.
Intended Audience
The intended audience is professional electrical engineers, project managers, and project engineers, involved in the specification, design, installation, and maintenance of purged and pressurized enclosures for electrical equipment.
Benefit to Attendees
Provide information on the methods for purging and pressurizing enclosures to prevent ignition of a flammable atmosphere.
Course Introduction
This 5-hour course presents the methods for purging and pressurizing enclosures to prevent ignition of a flammable atmosphere. By these means, electrical equipment that is not otherwise acceptable for a flammable atmosphere may be utilized in accordance with Article 500 or Article 505 of NFPA 70.
The course materials are based entirely on the NFPA 496, Standard for Purged and Pressurized Enclosures for Electrical Equipment, 2017 Edition. It will be necessary for the student to obtain a copy of NFPA 496, 2017 Edition. This is a very useful resource and is recommended that all practicing electrical or project engineers involved in the specification, design, installation, and maintenance of purged and pressurized enclosures for electrical equipment should be familiar with and up to date with the rules provided in this standard.
Course Content
This standard applies to purging and pressurizing for (1) electrical equipment located areas classified as hazardous by Article 500 or Article 505 of NFPA 70; (2) electrical equipment containing sources of flammable vapors or gases and located in either classified or unclassified areas; (3) control rooms or buildings located in areas classified as hazardous by Article 500 or Article 505 of NFPA 70; and (4) analyzer rooms containing sources of flammable vapors or gases and located in areas classified as hazardous by article 500 or article 505 of NFPA 70. You are required to obtain a copy and study NFPA 496, Standard for Purged and Pressurized Enclosures for Electrical Equipment, 2017 Edition. The standard is a useful tool that provides the methods used for purging and pressurizing enclosures every practicing electrical engineering professional should be familiar with.
The NFPA 496, Standard for Purged and Pressurized Enclosures for Electrical Equipment, 2017 Edition can be purchased from the following websites:
http://www.nfpa.org/
http://www.global.ihs.com/
NFPA 496, Standard for Purged and Pressurized Enclosures for Electrical Equipment, 2017 Edition.
Table of Contents
Chapter 1 - Administration
Chapter 2 – Referenced Publications
Chapter 3 – Definitions
Chapter 4 – General Requirements for Pressurized Enclosures
Chapter 5 – Pressurized Enclosures for Class I
Chapter 6 – Pressurized Enclosures for Class II
Chapter 7 – Pressurized Control Rooms
Chapter 8 – Pressurized Enclosures Having an Internal Source of Flammable Gas of Vapor
Chapter 9 – Pressurized Analyzer Rooms Containing a Source of Flammable Gas, Vapor, or Liquid.
Course Summary
This 5-hour course presents the methods for purging and pressurizing enclosures to prevent ignition of a flammable atmosphere. By these means, electrical equipment that is not otherwise acceptable for a flammable atmosphere may be utilized in accordance with Article 500 or Article 505 of NFPA 70.
Related Links
For additional technical information related to this subject, please visit the following websites or web pages:
http://www.ansi.org/
http://www.ieee.org/
http://www.nfpa.org
http://www.nema.org
Quiz
Once you finish studying the above course content, you need to take a quiz to obtain the PDH credits.
DISCLAIMER: The materials contained in the online course are not intended as a representation or warranty on the part of PDH Center or any other person/organization named herein. The materials are for general information only. They are not a substitute for competent professional advice. Application of this information to a specific project should be reviewed by a registered architect and/or professional engineer/surveyor. Anyone making use of the information set forth herein does so at their own risk and assumes any and all resulting liability arising therefrom.
