Recent content by ziptron

The snippet below is from Standard Z317 - Special Requirements for Heating, Ventilation and Air Conditioning in Health Care Facilities Can anyone provide a definition of what 'interlocked' means? The standard itself does not define it. I understand that the intent of this interlock is to...

Thanks! Urgh, I was actually missing those pages in my digital copy and I didn't notice.

Hey everyone, I keep hearing that within a dry sprinkler system water needs to be delivered to the inspector test valve within 60 seconds. However, I cannot seem to find this referenced in NFPA 13 or NFPA 2. I see some 60 seconds references within NFPA for combined dry and preaction systems...

Thanks everyone! Apart from all of your very clear and logical answers, I was also doing some research and came across some interesting findings which helped clarify this in my head. At first, I pictured the water front more like a horizontal wall. However I found some references which show...

That does not seem right, otherwise there would not need to be any reason to fill a large pipe slowly.

Hi All, We have a very long 8" diameter pipe that contains lots of twists and turns and the end of which is open to atmosphere. The pipe is normally empty, but it acts as a large discharge pipe from a tank. The tank discharge has a butterfly valve and when the tank is emptied, water flows...

I definitely agree with you. That is what I should do and what every prudent building owner should do (if property damage is at stake). I was just hoping that there was some sort of code/standard that says the same. Sort of surprising that I cannot seem to find one.

Hi Everyone, I am aware of a situation where an open to atmosphere Fire Water Storage Tank installed in a mechanical penthouse (not rooftop) of a building overflowed. It overflowed because a float switch failed to close. The overflow went into the mechanical room, flooded it and caused damage...

Sorry, it actually says 40 mill coating.. not sure where that 20 mill came from. Though in retrospect, even that seems a bit too thin based on what you guys are saying (and based on what common sense should have dictated to me from the start). Thanks everyone for your kind replies. This...

Ahh I see. Is there a rule of thumb as to what thickness constitutes a liner? I have here in my specs a '20 mill' coating. Seems somewhat thick to me.. hence the confusion.

Stupid question, but why are liners better? Is it just easier to get a continuous surface without holidays in a liner than in a painted epoxy? If you paint two times.. (two separate layers) and paint over the holidays, would you not have a good enough coating and be as good as a PVC liner for...

True, I see your point. What would you coat a gravity sewer with then?

I see several of you are suggesting pipe lining even though I mentioned that there would at times be some empty head space from the pipe not being full. Are there liners that will withstand that? Would they be an epoxy? If so, could you recommend some pipe lining products for me to look into...

Thanks for your quick replies. Pipe is rather large, 900 mm. Not many bends. It would be a new install. Going through a brain storm session on this project at the moment. I arbitrarily picked that ppm, but I'd like for it to sustain that based on some things that I am reading. Another thing...

Hi Everyone, As the thread subject says, I'm hoping to get some recommendations for a coating to coat a concrete force main and protect it from H2S gas produced by bacteria in the sewage. I expect H2S gas levels of around 400 ppm Past experiences/stories would be appreciated and names of...