×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

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

Jobs

Replacement of sprinkler heads

Replacement of sprinkler heads

Replacement of sprinkler heads

(OP)
Ok guys, in my jurisdiction(federal Buildings) we have few building that will need the sprinkler heads replaced due to age as per NFPA 25 para 5.3.1.1.1. and table 51.1.2 So here goes my question. How can someone make sure that the right heads are been put back on? My main concern is the K factor. Some of this heads don’t have hardly any markings. These buildings are old warehouse and storage spaces. Can you guys provide some guidance?

RE: Replacement of sprinkler heads

If they are that old, then there was only 1/2" and 3/4" sprinklers. You either have a 1/2" thread or a 3/4" thread. Pretty hard to mix those up. I would guess you would have the K5.6 heads for the 1/2" thread and 8.0 for the 3/4" thread.

Travis Mack
MFP Design, LLC
www.mfpdesign.com

RE: Replacement of sprinkler heads

PR,

Did you have the heads tested OR are you just replacing the heads based on age? A very high % of the heads tested do pass, so it maybe worth the $$ to have them tested.

****************************************
Fire Sprinklers Save Firefighters’ Lives Too!
Interested in “Hands On” Fire Protection Seminars with live fires visit www.chubb.com/lcu for information.

RE: Replacement of sprinkler heads

FM has found that the rule to replace heads when they reach a certain age is not neccesarily a good one. As others have noted, when these things are tested, they often come back fine. I know that doesnt help in the NFPA/Code world, but something to think about if you have some latitude to test representative samples at a lab.

RE: Replacement of sprinkler heads

As per NFPA 25, 2011 Ed this has been part of 25 for many years.

5.3.1.1* Where required by this section, sample sprinklers shall be submitted to a recognized testing laboratory acceptable to the authority having jurisdiction for field service testing.

5.3.1.1.1 Where sprinklers have been in service for 50 years, they shall be replaced or representative samples from one or more sample areas shall be tested.

****************************************
Fire Sprinklers Save Firefighters’ Lives Too!
Interested in “Hands On” Fire Protection Seminars with live fires visit www.chubb.com/lcu for information.

RE: Replacement of sprinkler heads

From NFPA 25 handbook on how the sprinklers are tested.

The sprinklers being tested undergo a procedure known as a plunge test. The sprinkler is inserted (or plunged) into a device known as a plunge test apparatus where it is exposed to an airflow that has a controlled velocity and temperature (see Exhibit 5.22, top). The temperature in the device is considerably higher than the operating temperature of the sprinkler. The sprinkler is pressurized with 5 psi (0.34 bar) of air pressure. The amount of time taken for the fusible element or glass bulb to activate is measured. If the sprinkler fails to operate in the specified amount of time, the sprinkler fails the test and all sprinklers represented by the test sprinkler (see Exhibit 5.22, bottom) must be replaced.

****************************************
Fire Sprinklers Save Firefighters’ Lives Too!
Interested in “Hands On” Fire Protection Seminars with live fires visit www.chubb.com/lcu for information.

RE: Replacement of sprinkler heads

If I remember correctly, there is a sampling procedure to test old sprinkler heads in order to determine if the existings heads need or need not to be replaced.

RE: Replacement of sprinkler heads


Yep all sprinkler testing procedures are all spelled out in NFPA 25.

****************************************
Fire Sprinklers Save Firefighters’ Lives Too!
Interested in “Hands On” Fire Protection Seminars with live fires visit www.chubb.com/lcu for information.

RE: Replacement of sprinkler heads

Can you still get copies of the original building plans which would comment on the types of sprinkler heads to be installed.

RE: Replacement of sprinkler heads

(OP)
Guys, thanks for all the replies, I know that the sprinklers heads Can be send for testing IAW NFPA 25 para 5.3.1.2 But you got to understand that this sprinkler system has the majority of the heads painted, corroded and they been subject to harsh environment, not to mention a mix match of heads. So I think complete replacement of heads is the best resolution, besides I will not have to visit this issue 10 years from now. I'm glad that the sprinkler head industry decide to put the SIN, this should make easier.

Travismack,

The sprinkler system is pipe schedule and there is a mix batch of ½ and ¾ so I will assume that the K factor you mention will be an appropriated replacement.

Chicopee

No a chance I having a hard time getting plans for buildings 10 years old.

Again guys thanks for the info.

Lou

RE: Replacement of sprinkler heads

Lou,

Now that we have a better picture as to what's going on, I agree with your evaluation. Painted and corroded sprinklers would fail immediately if sent to UL for testing

****************************************
Fire Sprinklers Save Firefighters’ Lives Too!
Interested in “Hands On” Fire Protection Seminars with live fires visit www.chubb.com/lcu for information.

RE: Replacement of sprinkler heads

"corroded and they been subject to harsh environment"


If these conditions are still present you may want to replace the sprinklers with a corrosion resistant sprinkler.

****************************************
Fire Sprinklers Save Firefighters’ Lives Too!
Interested in “Hands On” Fire Protection Seminars with live fires visit www.chubb.com/lcu for information.

RE: Replacement of sprinkler heads

Quote (PRinspector)

The sprinkler system is pipe schedule and there is a mix batch of ½ and ¾ so I will assume that the K factor you mention will be an appropriated replacement.

I'm not sure what the occupancy is and what the minimum required design is for the building. If you have any conditions in your mind that drive a density beyond OH1, I would suggest hydraulic calculations and changing some of the more remote branch lines. My experience has been limited to densities 0.20 GPM/square foot and less from any pipe schedule system.

RE: Replacement of sprinkler heads

(OP)
stookeyfpe,
I know, is a warehouse I bet the commodities have change a few times, you are correct that a complete survey of the system should be performed to ensure that the sprinkler system is design adequately to protect the facility. I have a hard time making this people understand the importance of proper design in reference with the hazards; in this case commodities. The notion is if the building is sprinkler then is good to go, this notion is shared by both the engineer department and the fire department. I preach to the engines company the importance of pre- fire plans, but I just get stare looks. Believe me is up-hill battle.



Thanks

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!


Resources