I've seen floor control assemblies (isolation valve, sometimes a check valve, waterflow switch, test & drain) in many different configurations as far as spacing of each of the components. I also understand that several manufacturers make an "all in one" valve assembly that can have all of these components. 

Is there any benefit to the operation of the waterflow switch by spacing out these components? I'm wondering if a steady stream from the test and drain that is further from the switch allows the waterflow switch to operate more consistently?

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Is there a reason why OS&Y would be better on backflow preventers for fire suppression systems over butterfly valves?

One application where we often must use the OS&Y is when the backflow serves a fire pump and we don't want to distort the flow and cause cavitation at the pump - but otherwise the butterfly valves are a major space saver. Just curious if others feel differently or if I'm missing a major benefit to the OS&Y type.

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Do you know what the protocol is if I am the engineer of record for an ongoing project when I change employers?  Am I obligated to continue to provide engineering services? 

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The 2015 Edition of the International Fire Code added some clarity for water supply for buildings with automatic sprinkler systems.

The Annex B material (not enforceable unless adopted) states:

B105.3 Water supply for buildings equipped with an automatic sprinkler system. For buildings equipped with an approved automatic sprinkler system, the water supply shall be capable of providing the greater of:
1. The automatic sprinkler system demand, including hose stream allowance.
2. The required fire-flow.

In the past I've heard several people say that only inside hose allowances are included when determining the total volume required (which sizes the water storage tank). Would you interpret this section of IFC to include both the inside and outside hose allowance?

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For standpipe hose connections within stairwells, does ADA (Americans with Disabilities Act) restrictions apply to the dimensions of hose valves coming off pipe? 

ADA - 2010 Standard

307.2 Protrusion Limits. Objects with leading edges more than 27 inches (685 mm) and not more than 80 inches (2030 mm) above the finish floor or ground shall protrude 4 inches (100 mm) maximum horizontally into the circulation path.

307.3 Post-Mounted Objects. Free-standing objects mounted on posts or pylons shall overhang circulation paths 12 inches (305 mm) maximum when located 27 inches (685 mm) minimum and 80 inches (2030 mm) maximum above the finish floor or ground. 
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In particular, I'm wondering if the 4" protrusion limit applies to standpipe hose connections off of a vertical standpipe, and if it does, if it only applies if the standpipe hose connection is pointed into the path of egress?

I would imagine there's some life safety experts that could explain this better than I surely am.

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Where concrete anchors are used for seismic bracing, they must be "prequalified". Is this just an additional listing that is required to meet ACI 355.2? 

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In general, when designing fire sprinkler systems with a fire pump, is your philosophy to only provide the minimum fire pump size that is needed to support your system, or do you often increase the fire pump size to decrease pipe sizes on the system?

How much are you typically willing to increase a fire pump size in order to benefit the pipe sizes throughout your project?

When I first learned about how to size a fire pump, I was told that if your system gets over 100 psi then you might as well size the pump to get as close to 170-175 psi on the system as possible - the reason being that the cost to upsize a fire pump is less than the savings associated with smaller mains and branch pipe.

I'm not sure that there's a hard-and-fast rule of thumb, but I'm just interested if other people use the same strategy or if it's entirely dependent on the type of job and size of the job.

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What is the ideal approach for fire sprinkler pipe to enter a building?

I find many engineer details show either an in-building riser (by Ames) or a ductile iron pipe with restrained pipe and fittings come under the building foundation and up into the building.

While this approach is acceptable, if we have the ability to coordinate with the structural foundation during design, would it not be better to drop the footing so that the fire sprinkler pipe can be sleeved through the vertical portion of the foundation wall?

I would think that running through the foundation wall would put far less pressure onto the pipe and joints itself. I understand when most installation/design work is completed is usually well after structural design, but when we do design upfront wouldn't this be the best-case scenario?

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On recent inspections I've seen many installations where an automatic ball drip is not provided anywhere on the pipe connection between the fire department connection and the check valve that serves the fire department connection. Is there an exception I'm missing or isn't that automatic ball drip always required?

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Have a unique scenario I'd be interested in other's take on. Eight-story building with automatic standpipes and a fully-sprinklered building. There's multiple scenarios where the building is close enough to an adjacent building that the exterior wall needed to be rated. In order to keep the fire resistance rating Tyco window sprinklers were installed in conjunction with glass to provide up to a 2-hour fire resistance rating.

The issue is that the sprinkler system experiences a working pressure of up to 220-230 psi, while the window sprinklers are only available as rated up to 175 psi.

We've proposed adding pressure reducing valve to the seven floors affected by this situation, but that introduces its own issues aside from cost. We've also suggested replacing the glass with a rated glass.

Are there other alternatives we haven't explored here? Would be interested in others' opinions.

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Without the context of a specific project or problem, when would you recommend creating a separate, detached fire pump house versus a fire pump room inside a building?

Is is purely a risk perspective? Do you recommend fire pump houses only when a pump is feeding multiple buildings, or a campus?

I've only had a few projects that used a fire pump house, and it has generally been in retrofit situations or when the pump is next to a water storage tank. In either case the pump house overall cost more than it would have should the fire pump room been within the building (even despite the simple construction of the pump house). Just curious on getting another perspective.

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We manufacture dust collectors and pre-pipe fire sprinklers within them with a couple fusible fittings.

We pressure test the pipe at our shop, however, when a contractor connects to them in the field, are there any code/standard requirements to check the system for leaks after connecting to the system?

We put on our drawings that the contractor should test for leaks, however, we're trying to determine what requirements exist for this application.

​The problem we're running into is that the connection is supposed to be made and checked before installing cartridges. If a leak occurs, the contractor could address and not get the paper cartridges all wet with running water down at the floor. In this last case they didn't, and I'm trying to address future installation of systems and make sure the contractor checks for leaks. 

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As best I can tell there's no listed bracing method for longitudinal seismic bracing for CPVC. Traditionally we've addressed this by placing a tee with a short pipe stub perpendicular to a main and braced that perpendicular pipe with a "lateral" brace, which acts longitudinally on the main. The downside to this is that it's not concentric to the main, but it's pretty close.

Is there a better way to brace CPVC pipe longitudinally?

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I've looked for it but I'm having a tough time coming up with the code section. Where does the requirement for a bell on the face of the building come from?

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From my uneducated perspective both concrete anchors and wood attachments that most people use in the field are not the prescriptive methods outlined in NFPA 13, but instead listed products that are easier to install.

In the interest of learning more about what's actually preferred by contractors, are there any good articles or book content anywhere that could help bring me up to speed on these various hanging attachments? Any help is appreciated.

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A project we're working on has an existing basement area that is broken up into many small existing rooms. Each room has varying ceiling heights and different grid directions.

The remodel that is going to be done will change all of these small spaces into three areas with a consistent new ceiling height that is about the average height of the existing ceilings.

If you are the engineer preparing bid documents in a scenario like this, would you call out for full pipe replacement, or only to modify the existing branch lines?

I would be interested in how others approach this issue prior to bid.

On one hand, modifying the existing system has the potential to save a significant amount of pipe, but could require some large stretches be raised to accommodate new ceilings and would require a good handful of labor to relocate sprinklers.

On the other hand, while an all-new pipe arrangement may cost more in material, it would be better able to coordinate with new HVAC ductwork and ceilings in the space and could possibly reduce the labor time with a pre-fabricated install.

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Hope everyone is having a great week. We're wrapping up this week's Daily Forum with a poll for use of software for hydraulic calculations. Don't see the poll below? Vote here.

If you would like to see your question (or poll) posted, please send it in or email us at info@meyerfire.com. Thank you!
​

Someone had asked about life safety Revit families and any recommendations. We do fire alarm design and are increasingly seeing BIM become the standard when working with architects.

Does anyone have any recommendations on where to find quality fire alarm Revit families? We're not manufacturer-specific design but are looking to improve our older basic devices.

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I've taken technical writing courses and have experience working with MasterSpec, US Military specifications, vendor specifications, and various ownership standard specifications.

I'm giving an internal training to our younger staff and I'm particularly interested in opinions from contractors and vendors who regularly read a variety of specifications for bidding.

What advice would you give for those who write specifications? I'd be interested in helping train our staff as well as improve myself.

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In my experience I've seen a handful of methods in Revit to create life safety plans, and in general they're all developed by the teams I've worked with using a combination of "rooms" and "railings" to calculate occupant loads and travel distances. 

Is there any third-party add-ins or software that others use that could possibly help streamline these efforts?

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For years on my code calls I have asked the Authority Having Jurisdiction what the maximum distance the nearest hydrant is allowed to be away from a building's fire department connection. I get answers that range from 50 feet to 400 feet or even more.

I was looking into the code basis behind this question, and the only applicable section that I found is the International Fire Code, Section 507.5.1.1 that addresses hydrant locations for standpipe systems:

"Buildings equipped with a standpipe system installed in accordance with Section 905 shall have a fire hydrant within 100 feet (30 480 mm) of the fire department connections. Exception: the distance shall be permitted to exceed 100 feet (30 480 mm) where approved by the fire code official."

Is there any relevant requirement for hydrants near fire department connections for sprinkler-only systems?

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Pressure Reducing Valve are commonly used to prevent excess pressure upon systems when supplies exceed the NFPA limit of 175 psi.

There has been much discussion regarding the 'application' of these valves when hydraulic calculations are being provided to the discharge of the PRV and determining the pressure margin available.

Currently, we have been instructed to calculate the system back to the PRV, use the PRV's friction loss calculator to determine friction loss through the valve and subtract that from the outlet setting to establish outlet pressure. This is then used as the available pressure at the outlet; minus the demand and you're left with the margin.

I'm not sure that I agree that the valves 'friction' loss need to be considered unless you are at a point where the PRV can no longer provide the set pressure (when the supply is unable to provide sufficient inlet pressure to overcome the internal friction loss).

Are there any 'papers' written for direction or other sources anyone might recommend?

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A dormitory has 1/2-hour fire barriers separating each residential unit. On each side of the 1/2-hour wall, penetrating the 5/8" gypsum, are shower valves that serve showers within bathrooms on each side.

The shower valves have the valve assembly itself and an opening that's covered with a metal escutcheon. These would qualify as a membrane penetration under the International Building Code.

For back-to-back vales in the wall, how is this commonly addressed to still maintain the 1/2-hour fire resistance rating?

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Amazon is selling fire sprinklers, escutcheons, and sprinkler guards. Some are UL Listed. But many are not listed for use together.

Because of the strict code requirements for installation and testing, is this appropriate marketing?

Who is liable for improper installation and system component failure? Who approves this?

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Have a project where the client is wanting fully-concealed sprinklers, but the project is insured under FM Global. FM does not approve any fully-concealed sprinklers as quick response.

However, under NFPA 13, light hazard spaces are required to have quick response sprinklers.

How do you normally address this conflict?

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