Skip to main content

Skylights vs Ceiling Compartments

Did you know that there are no depth limitations for skylights?  Only limitations on the area (32 sq ft) need to be considered.

Skylight is defined by Webster as "an opening in a house roof or ship's deck that is covered with translucent or transparent material and that is designed to admit light."

Excerpt from the 2010 edition of NFPA 13:
8.6.7 Ceiling Pockets Except as provided in and, sprinklers shall be required in all ceiling pockets. Sprinklers shall not be required in ceiling pockets where all of the following are meet: 

(1) The total volume of the unprotected ceiling pocket does not exceed 1000 ft3 (28.3 m3).
(2) The depth of the unprotected pocket does not exceed 36 in. (914 mm).
(3) The entire floor under the unprotected ceiling pocket is protected by the sprinklers at the lower ceiling elevation.
(4) The total size of all unprotected ceiling pockets in the same compartment within 10 ft (3 m) of each other does not exceed 1000 ft3.
(5) The unprotected ceiling pocket has noncombustible or limited combustible finishes. 

(6) Quick response sprinklers are utilized throughout the compartment. Sprinklers shall not be required in skylights and similar pockets in accordance with 8.5.7

8.5.7 Skylights. Sprinklers shall be permitted to be omitted from skylights not exceeding 32 ft2 (3 m2) in area, regardless of hazard classification, that are separated by at least 10 ft (3 m) horizontally from any other unprotected skylight or unprotected ceiling pocket. Skylights not exceeding 32 ft2 (3 m2) shall be permitted to have a plastic cover.

Popular posts from this blog

Installation of Diesel Fuel Tanks for Fire Pumps

After you have determined the size of fuel tank you need for a diesel fire pump, what are the general requirements for installation?  Assuming that you are under under the International Building/Fire Codes, you would go through the following chain of code references: IFC (2009 edition) 3401.2 Nonapplicability. This chapter shall not apply to liquids as otherwise provided in other laws or regulations or chapters of this code, including: ... (3) Storage and use of fuel oil in tanks and containers connected to oil-burning equipment. Such storage and use shall be in accordance with Section 603 . For abandonment of fuel oil tanks, this chapter applies. IFC (2009 edition) 603.1 Installation. The installation of nonportable fuel gas appliances and systems shall comply the International Fuel Gas Code. The installation of all other fuel-fired appliances,  other than internal combustion engines , oil lamps and portable devices such as blow torches, melting pots and weed burners, shall compl

Diesel Exhaust Requirements

The exhaust from a diesel engine driving a fire pump is an often-overlooked item.  The high heat put out by the exhaust is a hazard to occupants and can greatly contribute to overheating the room itself. NFPA 20 (2013 edition), section 11.5 covers "Engine Exhaust" and should be carefully reviewed. However as a starting point, the following items should be considered. Exhaust Discharge Location The first step is to determine where you are going to discharge the exhaust gases. NFPA 20 section 11.5.3 for "exhaust discharge location" has the generic common-sense requirements of do not discharge where you might hurt people, damage the building, or directed on combustible materials. But very little specific requirements are provided. There is a loose reference in NFPA 20 back to NFPA 37 ( Standard for the Installation and Use of Stationary Combustion Engines and Gas Turbines ). In addition, the International Mechanical Code (IMC) section 915.1 directs us back to NFPA 3

Fire Pump Rating (Size) Selection

Fire pump sizing is not like commercial pump sizing. We don't care about efficiency, and you order pumps in only specific sizes. This article touches upon some items to consider when picking a fire pump. In general, the first step is determining your system demand point. Discussion of how exactly you determine this is beyond the scope of this article and has a lot of nuance depending upon your site-specific needs. However, for simplicity let's assume that you have a dry-system in an attic with a demand point of 305 gpm (2535 sq ft x 0.10 gpm/sq ft x 1.20 overflow/imbalance factor). Rated Flow (gpm) Sizing The first item you must specify is the pump flow rate. Per NFPA 20 (2013 edition) table 4.8.2 pumps are only allowed to be listed with the following flow rates in gpm: 25, 50, 100, 150, 200, 250, 300, 400, 450, 500, 750, 1000, 1250, 1500, 2000, 2500, 3000, 3500, 4000, 4500, 5000 So with our example demand of 305 gpm, would you go with a 300 or 400 gpm rated fire pump?