Hi Engineers. I am asking for advise about the valve type at test connection on pressure-sensing lines. Further to NFPA 20 EDITION 2019 A.4.32(a), it marks the valve as globe valve. However, I cannot understand why it has to be globe rather than ball or gate.
I have three doubts, maybe four...
Hi cdafa,
I have talked with the clean agent about the opinion of placing the different type of detectors as per their own requirement. They told me they have never seen the design as it may reach the irregular placement of the detectors belonging to one fire suppression system, not detector...
Hi nuuvox,
Thanks for your advise. Actually I am on the way of solution #1. We found one company certified by NADCA located in Saudi no far from Egypt.
Solution #2 is pretty good but costs time. Considering that I would have to purchase many test materials (for swab test or vacuum test) and...
I have challenged our consultant and they refused to compromise with us since, as quoted from their words, "it is an international project and the Contractor should comply with project specs without excuse because the Contractor signed the Contract."
From my client's viewpoint, it is Lump-sum...
For "zone", ok I got your point.
We are using NFPA 72 as the installation standard, however smoke detector and heat detector have different spacings. For example, spacing of smoke detector is A, and spacing of heat detector is B. (A>B) So how long spacing should I apply in the case?
1. A
2. B...
Yeah they are still wanting heat detectors. In the beginning, the system specialist provided smoke detector and multi-criteria detector. Now the consultant is insisting smoke detector and heat detector as they think dusts or cigarette smoke may raise double knocks.
Regarding "zone", do you...
Hi cdafd,
Sorry to reply late. Hope you had a great summer.
Update of the above said issue:
Our clean agent system specialists don't agree with the Consultants' opinion of detector placement. And even different engineers in the Consultant have different opinions. (Most engineers in the...
Hi.
I work as a general Contractor in the construction of residential and office buildings. Our SPEC requires NADCA professionals to conduct duct cleaning, which we haven't done it for residential and office buildings before except for hospitals. And the most difficult part is that we cannot...
May I ask which state of AHJ you were? I always feel like to hear the opinion from AHJ about the issue.
We may use air sampling detectors in the room having high air flow.
The Consultant insists heat detectors in second circuit as they concerns smoke detectors in both circuit are more likely...
1. "The Consultant" is the Engineer as per FIDIC.
2. We have clean agent specialists hired. However they don't have clear answer about the reduction of coverage per detector as there is no clear answer in NFPA 72 or。NFPA 2001 or any code to specify the method of detector placement in clean...
Hi cdafd.
1. Yes. Same room. Cross zoned detection in one same room to activate clean agent suppression system. "Zone" here basically equals to "circuit of detectors" as my understanding. "Cross zoned detection" means two circuits of detectors to alarm and suppress the fire. (First circuit...
Hi ProSafPlant1.
Thanks for replying. It is so exciting to find someone having deep thought on the issue.
Yes, I have used the area of coverage per each detector for cross zoned system (fire suppression system) as below.
There are still some confusion not being settle yet:
1. How to determine...
I have read FSSA technical publication (DCG-01) and NFPA 72. However they doesn’t specify the detection placement methods of cross zoning detection in fire suppression system. As per DCG-01, it mentions that “historically, the industry has used an area of coverage per smoke detector of 250...
Hi cdafd,
It's a Lump Contract. So if the switch is to be added, it will increase our cost as a Main Contractor.
Background: This is a contract based on FIDIC yellow book 1999, and design part is outsourced back to the Engineer.
IFC (Info for construction) is from the Engineer. As IFC doesn't...
Very interested, but not in US. [upsidedown]
It should be a lot of fun to compare new NFPA with old ones and trace the development history of fire fighting system.
Is it necessary to provide Key Maintenance Switch (Disconnection Switch) for FM200 system?
As per Clause 4.3.6 of NFPA 2001 (2018.ED), disconnection switch (key maintenance switch) shall be provided. However, the SPEC doesn't specify key maintenance switch even though the SPEC follows NFPA...
Should FM200 cylinders be located on the concrete pad, or just on the slab?
As per IFC and SPEC, there is no requirement for location of FM200 cylinders. However the Engineer insists cylinders to be located on the pad, but I(the Contractor) cannot find the code reference in NFPA 2001. Is the...
