Can ESFR Be Used for Extra Hazard Group 2?

ust before I saw that discussion on the forum I was confronted with a nearly finished, similar situation.

A new technical plant for manufacturing of large-diameter high voltage cables. Huge amount of PE in the next-to-outer layer, and the sprinkler designer have based the fire protection on ESFR due to ‘’all the plastics’’ and generally large ceiling heights – variation between 40 and 55 feet – and a wish for ‘’maximum flexibility’’, by using table values for UUP for the respective ceiling height.

NFPA 13 – 2019 is to be used for the design.

The manufacturing process starts with a thin single wire and ends in an obvious UUP commodity.

In my mind this is mostly a production risk to be protected with spray sprinklers and density/area calculations, or CMSA-sprinkler parameters where the ceiling height permits it, especially as most of the fire load is moving cables, without automatic stop because the alarm could be undesirable or false.

It was said that cables during production would be directed up towards the ceiling, turn and twist on large diameter wheels, and also have large horizontal stretches before they run down into the next machine that may put on a new metal screening or extruding the outer PE layer before PVC or similar outer layer. Obviously a multi-stage production that in the end makes one large cable from 3 or more smaller cables.

As I have seen in earlier discussions, the understanding of the text in chapter 23.1.1 saying ‘’ESFR sprinkler shall be permitted to protect : …. Any storage arrangement OH1, OH2, EH1, and EH2 design criteria’’ must be vital for the understanding.

I don’t feel the actual situation is a storage arrangement, but if so, what is the target for the wording design criteria?

I suspect there will be ‘’longitudinal flue spaces’’ between the cables, transvers flue spaces are not possible. Some places there will be cable(s) in conflict with the minimum 300 mm horizontal distance from a storage suppression sprinkler rule.

However, this is the first time I have been presented for a ‘’ceiling only’’ option with 1 or 2 intermediate levels ESFRs having water shields.

And (luckily !?) someone had found the FM DS 8-9 Table 17b and put in K 480 storage sprinklers in the part of the manufacturing building with the highest ceiling.

Hopefully this is not the only cable manufacturing plant in the world, and I would greatly appreciate other views on this subject.

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Is there an FM Global requirement for a minimum safety factor in a hydraulic calculation?

We have a project that is following FM requirements, and the calculation "safety cushion" is coming in at 2 PSI.

We have looked through the FM Data Sheets, but cannot find anything to give a minimum criteria.

Thanks in advance.

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I have sprinklers at an exterior overhang over 100 feet above the floor (ground) it protects. There will not be anything stored directly beneath the overhang.

There is occupiable space above the overhang. It's noncombustible construction; a mid-rise office tower.

Questions have been brought up about heat collection, and the effectiveness of sprinkler spray: if there was a fire on the ground level, will enough heat be collected at the overhang 100-ft up in order to operate an intermediate temperature sprinkler that is 286 degrees F?

What will happen if there are high winds (common for this area)?

And if the sprinklers do discharge, will the water spray droplets evaporate before reaching a proximity of effectiveness?

Will a "cooling effect" even happen?

The AHJ will allow the sprinklers to be omitted. I'm not seeing anything specific to very high ceilings in NFPA 13 (2016).

My question to you all: Where can I find the science to backup their decision?

Do you know of any resources where this scenario has been studied, evaluated, or fire-modeled? (FM or non-FM?)

Obtaining a PE review is not a desirable option. (I am aware that FM datasheets address this scenario as requiring sprinklers.) Thanks in advance.

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Would the rack storage of non-encapsulated, Group A, unexpanded plastic commodities, stored in solid plastic containers (totes), be considered cartoned or exposed?

NFPA-13 Section 3.9.1.1 defines cartoned as storage consisting of corrugated cardboard or paperboared containers fully enclosing the commodity.

NFPA-13 Section 3.9.1.13 defines Exposed Group A Plastic Commodites as those plastics not in packaging or coverings that absorb water.

This leads me to think that any rack storage of Group A unexpanded plastics within solid plastic containers should be considered exposed, as these are not cardboard or paperboard nor does plastic absorb water.

Thanks in advance!

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This feels like a silly question, but we have high-piled, non-combustible storage, with open-grate or solid level single/double row permanent racks with Extra Hazard Group 2 overhead system.

I'm trying to identify the actual code verbiage that says nothing is required from an code/NFPA standpoint.

The product is metallic car parts with no added materials, just exposed solid metal, no plastic gaskets or spacers, etc.

The 2015 IFC is the highest code in my jurisdiction, so starting with that, Chapter 32 is for High-Piled "Combustible" Storage and provides no avenue for code justification.

NFPA 13-2013 defines "Noncombustible Material & Automotive Components on Portable Racks" but also gives no criteria for non-combustible storage.

FM Global Data Sheet 8-1 actually lists noncombustible as a commodity classification, unlike NFPA 13, but does not provide a criteria stating no coverage.

Is this just the simple scenario where code or NFPA standards don't list a requirement or criteria because it just doesn't require anything?

Again I feel like it's a silly question given the commodity but I believe the only rules to follow would be obstruction rules and distance from deflector to storage.

Thoughts?

Thanks in advance.

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Does FM Global design criteria weigh in on whether skylights require protection?

Do they simply adopt the same provisions in NFPA 13 in this regard? Or is there some devation?

I can't see any allowance for omission of sprinkler protection for skylights in Data Sheet 2-0.

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I have a building with FM Approved doors, but I can’t identify the fire resistance rating.

We have a fire label but nothing else (see the image). Is there a minimum fire rating for any FM Approved door?

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I have a project with a workshop space that has a ceiling height of 70-feet from floor level.

How do I approach sprinkler selection & system type for this height?

Does NFPA 13 have a ceiling height limitation?

I see a couple of tables in FM Data Sheets, but is this the only source for protection at these heights?

Thanks in advance.

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NFPA 13 does not allow ESFR protection for shelf or bin box storage. I can see the logic, and this has been in the code for years.

However, FM Data Sheet 8-9 does allow ESFR protection for shelf and bin box. I can protect shelving up to 15-feet with 0.85 over 2,500 sqft but I can't protect it with K25 at 70 psi.

Any insights on the logic here? Has testing been done that supports this one way or another?

Thanks in advance.

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I have a high-piled storage project that falls under both the International Fire Code and FM Global. We are using FM Storage Sprinklers.

Are smoke and heat vents required?

Under the International Fire Code Chapter 32, I am directed to Section 910 for smoke and heat vents. Section 910 states that if ESFR sprinklers are used then smoke and heat vents are not required.

I have read several definitions for ESFR, and they appear to be essentially the same as FM Storage Sprinklers.

My problem is that per the interpretation, if I follow FM Global Data Sheet 8-0 and use Storage Sprinklers, then per IFC Section 910.3 I must have the architect add smoke and heat vents for every 50,000 sqft of the buliding.

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I recently investigated some fire doors at one of our older buildings and saw they have an FM Approved label on them instead of a common UL Listing. I'm used to the UL listing label which clearly states the fire rating in minutes or hours. The FM label I saw gives some outdated ASTM standards and references a CABO report but doesn't clearly state the fire rating.

Does anyone have experience with the FM Approved fire door labels?

Based on my research, FM stopped approving fire doors a while ago. Thanks in advance.

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I am interested if anyone is aware of any research or article that provides guidance on the lowest water velocity that is acceptable for performing a C-factor calculation for a 6” pipe?

I am curious if there is a lower flow velocity where the Hazen-Williams equation may not be valid.

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NFPA 13 has the hydraulic remote area reduction for use of Quick-Response sprinklers for wet, light/ordinary hazard, low(er) ceilings without pockets.

Does FM Global recognize anything similar for the use of quick-response sprinklers, or is their HC-1, HC-2, and HC-3 categorization the minimum remote area size regardless of sprinkler RTI? 

​I've checked FM Global Data Sheet 2-0 and 3-26, but have yet to find anything similar in nature.

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I had always thought that couplings didn't need to be calculated under NFPA 13, but I'm reviewing a set of calculations which show 1-foot of schedule 40 equivalent for each coupling. This is for a 4-inch main with roll-groove couplings. Any ideas?

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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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For a flight simulator inside a larger building, what sprinkler density do you feel would be appropriate for this hazard?

The simulator will be its own contained unit, so the top will likely shield water spray from sprinklers above and prevent water penetration to the inside, much like a vehicle fire would in a parking garage.

NFPA 13 does not address simulators, nor does UFC 3-600-01 or FM Data Sheets (as far as I can tell). In my opinion the closest hazard I can gather would be vehicles in a parking garage which carry an Ordinary Hazard Group 1 designation under NFPA 13 (2016) 5.3.1 and A.5.3.1.

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