A dormitory has residential rooms which house two students. There is a traditional sleeping area approximately 12 ft x 12 ft, and a hallway with a bathroom and closet in-between the sleeping area and the main corridor.

Separating the sleeping area and the unit hallway is an opening about the size of a door opening (but with no door). This project is still in design.

How shallow would the header on this opening need to be (distance from the ceiling), in order to avoid requiring a smoke detector in the sleeping area and the hallway?

Posted anonymously for discussion. Discuss This | Submit Your Question | Subscribe

An atrium houses furniture in varying arrangements at the floor level, of which heat transfer is a primary concern between combustible objects. Determine the rate of convective heat transfer (in kW) between a 31 sqft section of wood-faced wall at 22 deg C with an effective heat transfer coefficient of 0.54 kW/m^2K and a burning surface at 425 deg C.
a. 218 kW
b. 627 kW
c. 6746 kW
d. 7115 kW

Solution | Posted 09/02/19

For those that do freelance design, what avenues would you recommend to get professional liability insurance? I would think there'd be some insurers that understand our industry more than others, which could be a better starting point than googling insurance brokers.

I'm in the same boat for healthcare too - do you go with the open marketplace or are there any trade groups that offer group plans (like an NFSA or AFSA)? Just looking for starting points to make sure I vet all avenues. Thanks in advance for any input.

Posted anonymously for discussion. Discuss This | Submit Your Question | Subscribe

​​Annual inspection of wet barrel hydrants must include all of the following except:
a. verify marking of hydrant
b. verify outlet thread condition
c. verify access to hydrant
d. verify cracks in hydrant barrel

Solution | Posted 08/30/19

Does anyone have good resources (articles, design guidance) for fire suppression systems protecting new marijuana grow facilities?

Posted anonymously for discussion. Discuss This | Submit Your Question | Subscribe

​Determine the flow (in gpm) through a residential sidewall K4.2 sprinkler at 10.1 psi.
a. 13 gpm
b. 18 gpm
c. 21 gpm
d. 42 gpm

Solution | Posted 08/29/19

When there's a cloud ceiling that requires sprinklers above and below, how does that play out in the hydraulic calculations? NFPA 13 23.4.4.5 implies that we should only include the upright heads at the ceiling and exclude the pendants in the floating clouds from the remote area calculations. Do you think that's the right call?

Posted anonymously for discussion. Discuss This | Submit Your Question | Subscribe

Solution | Posted 08/28/19

Our project has a proposed layout includes convenience stairs next to a corridor that serves restrooms, utility spaces, and doors to large open office areas. It's a B-occupancy subject to NFPA 101 requirements.

As a side note, the International Building Code (2018) makes it clear that two-story openings are permitted in occupancies other than I-2 and I-3 when they meet certain limitations, per section 712.1.9. One of the limitations it that is it not open to a corridor, but that's in Group I or R occupancies only. Group I and R occupancies require special treatment for corridors.

NFPA 101 has similar provisions for Convenience Openings (Section 8.6.9). One of the requirements is that "such openings shall be separated from corridors", per section 8.6.9.1(3). If corridors in a building are not required to be separated (such as for an open-office B occupancy), does this requirement still apply, or is this section saying that we have to have rated corridors whenever we have convenience stair openings?

   8.6.9 Convenience Openings.
  8.6.9.1 Where permitted by Chapters 11 through 43, unenclosed vertical openings not concealed within the building construction shall be permitted as follows:
   (1) Such openings shall connect not more than two adjacent stories (one floor pierced only).
   (2) Such openings shall be separated from unprotected vertical openings serving other floors by a barrier complying
with 8.6.5.
   (3)* Such openings shall be separated from corridors.
   (4)* In other than approved, existing convenience openings, such openings shall be separated from other fire or smoke compartments on the same floor.
   (5) In new construction, the convenience opening shall be separated from the corridor referenced in 8.6.9.1(3) by a smoke partition, unless Chapters 11 through 43 require the corridor to have a fire resistance rating.
   (6)* Such openings shall not serve as a required means of egress.

Posted anonymously for discussion. Discuss This | Submit Your Question | Subscribe

​In which of the following scenarios is neither explosion protection nor suppression system required?
a. Flammable paint warehouse mixing rooms where open transfer of paint occurs
b. Dust ventilator equipment where the dust density can be above its lower flammability limit
c. Mechanical room where service equipment is subject to explosion
d. All of the above require either explosion protection or suppression systems

Solution | Posted 08/27/19

The Leaderboard lists the top total scores for the most recent three weekly exams for PE Prep Series participants. 
See the entire scoreboard here.
​

Want to join in? It's not too late - the PE Prep Series is the ultimate PE Prep tool. It's a series of 1-hour, 10-question simulated PE Exams offered weekly with solutions immediately following each exam. Learn more here. ​​​​Every week of the series is retroactive so you can still test yourself with past week exams

I have a warehouse with a roof 20 feet above. The designer has branch lines hanging under the ceiling joists. He has 10 foot drops of 1-1/2" sched 40 to an ACT ceiling over office spaces. We are in a "D" seismic design category building. I am unable to find any requirements for vertical restraint in the NFPA 13 or ASCE 7-10. Can anyone direct me? 

Posted anonymously for discussion. Discuss This | Submit Your Question | Subscribe

Solution | Posted 08/26/19

Does a hydrostatic test need to be performed for a project that just has relocated sprinklers, or just a leakage test subject to working pressure?

I'm having trouble finding where NFPA 13 gives guidance on this. Any help is appreciated.

Posted anonymously for discussion. Discuss This | Submit Your Question | Subscribe

Solution | Posted 08/23/19

In NFPA 13 under "Location of Hangers on Branch Lines", Section 9.2.3.6 (2016 Edition) states that "wall-mounted sidewall sprinklers shall be restrained to prevent movement."

This section does not relate to seismic restraint, and annex material clarifies as much.

How is this sidewall-restraint typically achieved? 

Many sidewall sprinkler installations have an armover and a drop that goes down the wall before a reducing elbow serves the sprinkler in the wall, and I don't recall ever seeing a means to restrain the pipe (or sprinkler) for steel jobs.

Posted anonymously for discussion. Discuss This | Submit Your Question | Subscribe

Solution | Posted 08/22/19

Do you have any thoughts or input on the interior exit stair penetration limitations of Section 1023.5 of the IBC? 

I have someone contending that you aren’t allowed to run a “bulk feed” main into a stairtower and then back out again on a different level.  They claim that 1023.5 limits penetrations only to MEP equipment that serves the stairwell itself.  I contend that, especially as clarified in the 2018 edition (although I contend that it was always the intent), any fire protection system is allowed to penetrate such a stairtower as needed, as long as the penetrations are correctly firestopped etc…
 
The confusion comes from the 2015 edition, which reads (emphasis added to indicate the confusion that I think this person is having):

“Penetrations into or through interior exit stairways and ramps are prohibited except for equipment and ductwork necessary for independent ventilation or pressurization, sprinkler piping, standpipes, electrical raceway for fire department communication systems and electrical race-way serving the interior exit stairway and ramp and terminating at a steel box not exceeding 16 square inches.  Such penetrations shall be protected in accordance with Section 714.  There shall not be penetrations or communication openings, whether protected or not, between adjacent interior exit stairways and ramps.”
 
I believe that that person is seeing that “serving the interior exit stairway and ramp” portion of that snippet, and they are applying it to everything.  However, I contend that that is actually applying specifically to “…and electrical race-way serving the interior exit stairway and ramp and terminating at a steel box not exceeding 16 square inches”.  I think that the person is cherry picking what they want it to say, although it is somewhat confusing the way it’s all written on one line.  I believe that if that person really wanted to apply this verbatim, then you would not even be allowed to have combined standpipes that feed sprinkler systems outside the stairwell, or even dedicated sprinkler risers in the stairwell wouldn’t be allowed to serve any floor area outside the stairwell.  Basically any sprinkler riser in a stairwell would only be allowed to feed that specific stairwell…  I think it’s clear that this is not the intent of the code.

Read More Here

Posted anonymously for discussion. Discuss This | Submit Your Question | Subscribe

Solution | Posted 08/21/19

NFPA 13 Section 8.15.4 (2013 Edition) requires certain types of unenclosed floor openings to be protected with closely spaced sprinklers where sprinklers serve as an alternative to the enclosure of the vertical opening. 

What method do you use to determine if the opening requires enclosure, and thus closely-spaced sprinklers? 

As a sprinkler designer, I may overlook something in the Building Code that allows the unprotected opening, or vice versa.

A pre-bid RFI to the architect seems to be the best course, but it would be nice to have something to hang the hat on before the bid is submitted.

​​Posted anonymously for discussion. Discuss This | Submit Your Question | Subscribe

Solution | Posted 08/20/19

​Want to join in? It's not too late - the PE Prep Series is the ultimate PE Prep tool. It's a series of 1-hour, 10-question simulated PE Exams offered weekly with solutions immediately following each exam. Learn more here. ​​​​Every week of the series is retroactive so you can still test yourself with past week exams

Correction on the Week 11 Exam: Question #8 asked for the carbon dioxide quantity in kilograms but the solution was in pounds. The correct answer is 156 lb, or 71 kg. This has now been updated in the series for future users.

I've heard from several installers that small diameter schedule 10 pipe (such as 1-1/4") will warp if there's more than two welded outlets made onto it.

Would any installer/contractors weigh in on how you best combat this problem?

I could see larger diameter (1-1/2" or more) schedule 10 as a possible solution, which also helps hydraulics. I could also see voluntarily going to schedule 40 as a possible solution. Cutting the pipe into shorter segments and adding couplings would also help, but I could see the cost adding up for the labor, couplings, and additional hangers.

​​Posted anonymously for discussion. Discuss This | Submit Your Question | Subscribe

Solution | Posted 08/19/19

The International Building Code requires identification of fire partitions, barriers, or fire walls with 3" letters identifying the wall itself.

I've seen (especially in hospitals) labels for each through-penetration with a UL Listing sticker right below each penetration. Is this a requirement by code, or just a hospital standard?

​​Posted anonymously for discussion. Discuss This | Submit Your Question | Subscribe