This month's question regards FPL wiring.
Q. My local inspector told me I couldn’t use FPL wiring in conduit (raceways) because it wasn’t listed for being installed in conduit. I always feel less than professional when some of these guys spit out rules with such conviction — I feel like I should be begging for forgiveness or claiming insanity.
A. Saturday Night Live used to do a bit with Jane Curtin and Dan Aykroyd called “Point-Counterpoint,” where they would debate a political issue. Jane always stated her position first — in this case she had installed FPL wire in conduit and praises the flexibility in its applications. When it was Dan’s turn to state his “counterpoint,” he would always respond by first saying “Jane, you ignorant slut…” followed by flawed reasoning and strongly stating his opinions as if he knew what he was talking about. Dan was always able to get away with imposing his odd views because he always had the last word.
In this reader’s case, the last word will be by the person that is able to prove they are correct.
Finding the Answer in the NEC
The National Electrical Code (NEC) is the wiring standard referenced by NFPA 72. To locate the information you need in the NEC, first, go to NEC Article 760 — since that section is the NEC’s starting point for all their fire alarm wiring rules. Article 760.3 clearly states that “Only those sections of Article 300 referenced in this article shall apply to fire alarm systems” (Don’t go looking for trouble).
Use the year/edition of the NEC referenced in your local or State Building Code. I will use the 2011 edition in this example. Article 760 has three “I” sections. Section I is a short general section with definitions and a few generic rules that send you to other NEC sections that may also apply. Skip Section II, which covers “Non- Power-Limited Fire Alarm (NPLFA) Circuits.
Section, III, named “Power-Limited Fire Alarm (PLFA) Circuits” is the applicable section. Remember, your local inspector’s issue is with the PLFA wiring method you used. Scan down the section III headings until you see; “760.154 Applications of Listed PLFA Cables.” For NFPA 72 users, it can start to seem a little convoluted at this point, but I will walk you through each step.
Section 760.154 reads “PLFA cables shall comply with the requirements described in either760.154(A), (B), or (C)…” This means that you are in compliance if you follow the rules of “either” of the three sub-sections of 760.154, namely A, B or C. It seems section A is for FPLP (plenum) wire, so skip this. Section B is for FPLR (riser) rated wire, which also isn’t applicable to your situation. Section C reads, in part, “(C) Other Wiring Within Buildings. Cables installed in building locations other than those covered in 760.154(A) or (B)(which we just read to beFPLP and FPLR) shall be as described in either (C)(1), (C)(2), (C)(3), or (C)(4).”We are getting close since only one type of cable remains unaddressed.
Section 760.154(C) has a list of rules numbered 1 through 4. No. 1 indeed completes the list of three kinds of FPL wiring being covered by 760.154 — namely plain old “FPL” line – that’s what you used! The second rule listed under part (C) covers conduit: “Cables shall be permitted to be installed in raceways.” The advantage of using plenum or riser wire is that conduit is not needed; however, since it states that FPL “shall be permitted to be installed in raceways” it too can be used for risers or in plenum spaces.
It is important to note that when codes and standards state that equipment, methods, or procedures “shall be permitted”, it is speaking directly to the code official and prevents them from ‘ruling’ otherwise. “Shall be permitted” is not open to interpretation and the code official has no choice but to comply or legally pass a local ordinance to the contrary. It is always wise to check for local ordinances before applying any state codes or national standards.
Burst Pipes — New Monitoring Source?
A separate issue that has become more prevalent lately is a result of the changing climate. Record low temperatures and high winds have caused many sprinkler pipes to burst across the country — even in some regions previously thought to be immune from such extremes.
Public libraries, as well as private companies, have suffered greatly from the resulting water damage. The sheer number of these calamities have caused clean-up and restoration companies to be overwhelmed.
In many cases, the damage could have been avoided had a low-temperature supervisory switch been provided in at-risk areas or even at the riser itself. Then when the customer is notified of a low building temperature (due to any number of causes), someone could turn off the sprinkler water supply and/or provide some type of emergency heat.
This is your chance to offer this additional monitoring service. Will it make you big bucks? Probably not, but it can be the answer they were looking for, and might get you in the door to future customers.
Greg Kessinger is SD&I’s fire alarm and codes expert and a regular contributor. Email him your fire & life safety questions at [email protected].