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What I see on MSDSs, deluge or mist is great for cooling/extinguishing ammonia containers. Of course the specific risk and site sould be analyzed by chemical risk expert in charge. There may be some issues with ammonia cloud control, icing of important parts, foam requirement, etc, but in...

Would better refer it as 100% of design agent amount with more specific explanation about the trim depending of the system technology. If possible delete that requirement or change it as a more specific ítem optional cost information depending on clean agent system. A normal fast bidder would...

If you have a hydrant or sprinkler grid where noise, vibrations or pressure loses where a high Reynolds number would be an issue or if you want a "balanced" system, it is a desirable option to consider velocity limits, but not a code requirement. For example, a well code design may worry...

It may be complemented with local or AHJ requirements. You go with class III and maybe a removable restricting device on 1.5 hose connection or hose valve may solve the class II req.

Most of the detector´s electronics are not for condensing wet environments. I have used aspirating type Vesda with a condensate trap (piece of transparent pipe with a manual drain before the device) and works fine so far (tropical forrest área power plant). It collects some cm of water on wet...

Yes, without the CA the required thickness would be 2.02mm. With a ca of =0, 6-Sch40 holds 1150psi aprox. With a ca of =2mm, 6-Sch40 holds 810psi aprox. This is approximate, many variables: check on respective ASTM if mill tol. is 12.5%, allowable stress is still 4.6kpsi on the current code...

I´d also choose B31.1 (2007) as an aprox. reference point. For a 6" inch pipe with an arbitrary 2mm corrosion allowance, the required thickness for 20bar at room temp is 4.02mm and 6"Sch40 is actually 7.1mm, so no problem with your pressure with SCH40. Smaller diameter same Sch are safe too and...

On NFPA 72 a positive alarm procedure allows on certain conditions to prevent automatic alarm. Of course not all facilities have personnel to respond in such way, so not always apply and only if AHJ allows.

That is what I was seeing, depending on how big is the system between the pump and the dry valve, you have a wet system to consider or not. Where is the limit? Other point is if the DPressure of pump at the start is too big, is it recommended to have JP to define a good star set point for the...

I understand that downstream the dry valve the jockey pump is not involved nor needed, my doubt is if if the water supply (upstream) this valve need a pressure maintenance pump.

So the line between the pump and the upstream side of the preaction valve is also dry? If so when the pump starts the water would fill or refill violently the pipes, is that Ok? I am missing something?

Good question. Don´t have the answer. The main pump start point refers to JP set point to define start. If there is no JP how do you define start for the main? How do you keep the pipe upstream of the control (preaction) valve full?

Thanks. By a google glance. What I´ve found is that the NFPA 30 is too general for this. And for the transmission lines it is supposed to be a responsibility of the power company to define the respective safety measures. So that´s what I´m supposed to be looking for.

Hello dear everybody. Can somebody help me to find info or give hints on what security distances should be considered from a fuel oil #2 tank AST atmospheric fixed roof tank (28m diameter) from a power transmission line. (No problem, if not in USA, any country guidance would be appreciated).

Always remember that the NFPA is not a design guide, it is a code or standard. It is easy to loose the North on this because the NFPA 13 or others include drawings, appendixes, etc., with many design guiding issues, but if you want to be a good fire protection engineer, do engineering, never...

I suppose that it is because it is easy and cheap to get leak tight threads on 1.5" or less, and on small sizes in general the amount of joints tend to multiply.

Transfomers do get fire, explosions are less frecuent. An overcharge or lightning stryke will cause an overpresure leak and sprayed oil droplets will easily lit fire with lots of heat. Remember that fire protection on a transformer is not related only to the risk of falure, it is mainly...

Thanks a lot stookey and cdafd.

Not sure if I got the idea clear. But, if there is a pump and the pump goes on churn, will the p relief valve at the pump work fine?, or do you need another preliefv at this pipe section?. I understand that the small PReliefV is for no flow relief when valves are closed for example. Just a point...

Oh I found it. NFPA 24, 8.7. Domestic service use prohibited. The use of hydrants and hose for purposes other than fire-related services shall be prohibited.". ...f@#*!.