We are working on a mass notification system design. We have always called for any speaker/strobes in close proximity to the microphone to be shutoff during live announcements to prevent feedback.

Is there an actual recommended distance away that all speakers located within this distance should be shutoff? 

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We have been asked if a 20+ year old wet pipe sprinkler system we installed into a paint application room is the correct method of protection for a specific paint product that is currently being used.

The MSDS sheets for a few of the products they now use indicate protection with dry chemical, foam, or water fog.

I have been told that the MSDS sheets typically refer to the product as its being stored and not necessarily as its being applied. The storage is not happening in this room of course, but in approved fire-rated storage cabinets outside the area. None of the typical requirements for alternate protection are met per NFPA 33.

Basically other than the product data sheets, this is a run of the mill paint application area. Nothing automated or fancy.

Anyone have any experience with a similar situation?

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Do liquid nitrogen storage rooms need to be fire-resistance rated?

According to NFPA 55 (2016 Edition) Section 6.4.4, gas storage rooms need to be 1-hour fire rated, but it just seems odd since nitrogen can be used as an extinguishing agent.

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When applying NFPA 13R to a mixed-occupancy (R-2 and S-2) building, what is the definition of "incidental"?

The building in question is three stories of residential over a parking garage designated for residents only. Each residential floor is approximately 2,000 sqft and the garage is approximately 3,000 sqft. The building is type V-A (wood, combustible) throughout.

IBC 2015 Section 509 defines incidental as constituting less than 10% of a given floor.

Does this entire building require a full NFPA 13 system?

If possible, please provide a code basis, thank you!

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My question is when the discussion of dirty sprinkler heads comes up I get told only lint , hair and fuss count.

What I see quite often is discoloring from what I assume oil running down the pipe to the head. I also often see the red glass turned to black or gray.

Do these sprinklers need to be cleaned, and if so, how is it done?

​Air or vacuumed doesn’t always work.

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Does anyone have experience installing a heat detector in a cold environment (~ -40 degrees C or F)?

I'm thinking a rate-of-rise detector would probably be the right type based on what I've read but having problems finding a cut-sheet that supports that operating environment. Normally this type of space would get a dry sprinkler but some things have led to trying to think "outside the box" for this project. Thanks in advance.

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In NFPA 13 (2007 Edition) Section 8.15.5.5 is the term "passenger elevator" specifically different from a Freight Elevator?

NFPA 13 Section states that sprinklers are not required for noncombustible hoistways where the car enclosure meets ASME A17.1, but it states specifically "passenger elevators".

Does this mean that a hydraulic freight elevator will definitely need a sprinkler at the top and at the bottom of the shaft?

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Under NFPA 72 fire alarm manual pull stations are required on both sides of grouped openings over 40-feet in width and within 5-feet of each side of the grouped openings.

What about grouped loading bays or loading docks? Are manual pull stations required on each side of grouped overhead doors?

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We are inspecting an existing fire sprinkler building for an upgrade to an Extra Large Orifice (ELO) system.

We performed a hydrant flow test and noticed a 14 psi static loss between the hydrant, 185-ft of 8-inch ductile, 2 elbows and 8 feet of elevation rise to the supply side of the RPZ backflow preventer.  We recorded 73 psi at hydrant and 59 psi at the number 1 test cock on the RPZ while static.

I spoke with the water authority and they confirmed no meter or check valve on the 8" fire line; it is straight into the valve room plus 2 elbows. The building is 20 years old and the pump test provided 120% of rated capacity.

Any idea how the static pressure inside the building is 14 psi less?

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We have a project where we're not sure about how to address protection of movable storage racks.

The cold storage facility requires a double-interlock pre-action system where the temperature can reach down to -4 deg F (-20 deg C). The storage consists of movable racks, 39 feet (12 m) tall, with a roof height of 46 feet (14 m). 

Our biggest concern would avoiding in-rack sprinklers, since the racks are intended to be moveable. 

Our understanding is that NFPA 13 considers movable racks as multiple row racks but there's not clear guidance there. We looked into ESFR as an option, but believe ESFR are not listed to be used with a pre-action system.

Is there a recommended solution/design path for ceiling-only protection on a double-interlock pre-action system?

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I have a high-rise 24-story residential condominium building. The construction is non-combustible, but the local jurisdiction is requiring balcony protection regardless of what NFPA 13 says on the matter. 

Am I correct in thinking of using residential heads in the units, as well as in the adjoining corridors and the balconies, providing that I meet the minimum 0.10 gpm/sqft density required for an NFPA 13 system?

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Around here we're all about promoting the industry by bringing together a community of experts and sharing best practices. It's too important of an industry not to promote.

We like to celebrate that efforts where we can, and today I'm happy to announce the overall Top Ten Contributors of 2020. These experts have, on average, shared quality expertise throughout eight months out of the year and have help countless people, like myself, learn a little more each day. The Forum wouldn't be what it is today without all of the commenters and especially these professionals:
​

We'll be sending out 2020 Top Contributor Plaques as a small thank you for contributing to the great conversations that do nothing but help the industry learn and grow.

If you happen to be Colin, Casey, or Mike, please email me at info@meyerfire.com so I can get your thank you gift headed your way. 

A couple of questions about an electric vertical inline fire pump:

(1) Is it necessary to build a rated room around a fire pump that is located in a boiler room that is already 2-hour rated construction?

(2) Is it required to have a concrete base poured below a vertical fire pump if we can bolt the pipe flange stand to a concrete floor?

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Does anyone have any insight to the sprinkler design criteria requirements you would use to protect a small volatile manufacturing facility?

The building is a standard pre-engineered metal building with z-purlins, is insulated, uses corrugated siding, etc. It stands 20-24 feet tall at the peak. Any help is appreciated.

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