Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here


Positive Pressure Ventilation for Electrical Rooms

Positive Pressure Ventilation for Electrical Rooms

Positive Pressure Ventilation for Electrical Rooms

Can someone give me some guidance and resources on how to design a positive pressure ventilation system (not airconditioning) for an electrical room.  Things I'm looking for:

1.  How much pressure is required to successfully keep out dust?
2.  Types of filters available and allowable velocities through the filters.
3.  Are inlet and outlet fans needed or can a fan blowing into the room alone be sufficient?


RE: Positive Pressure Ventilation for Electrical Rooms

Your design parameters are covered in ASHRAE Standard 62-2001, "Ventilation for Acceptable Indoor Air Quality."
To secure a copy of ASHRAE Standard 62-2001 or any of the other ASHRAE documents referenced in this guide, contact:
    American Society of Heating, Refrigerating and
    Air-Conditioning Engineers, Inc.
    1791 Tullie Circle NE
    Atlanta, GA 30329
    Phone 1-800-527-4723 — publication orders only
    Phone 404-636-8400 — technical inquiries
    Fax 404-321-5478
    Web www.ashrae.org

Ventilation Rate Procedure (Section 6.1) presents "...one way to achieve acceptable indoor air quality", namely, supplying each occupied space with ventilation air of specific quality and quantity. Outdoor air is used to dilute anticipated contaminants to acceptable concentration levels.

In contrast, the Indoor Air Quality Procedure (6.2) presents "...an alternative performance method...for achieving acceptable air quality" by quantitatively describing acceptable indoor air quality. It sets limits on the concentration of known and specifiable contaminants in an effort to achieve acceptable indoor air quality in the occupied zone in a more direct way that the Ventilation Rate Procedure. More specifically, the Indoor Air Quality Procedure sets concentration limits for 10 contaminants, prescribes subjective analysis to determine acceptable odor levels, and describes the use of treated recirculated air to reduce the minimum outdoor airflow rates presented in the standard

Your internal pressure must over come external wind pressure.

Inlet fans can be used for pressurized rooms

Also refer too NFPA 90A

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close