How to Determine Obstructions with Beam Rule?

One of the most common and basic issues many of us encounter in fire sprinkler design or during on-site review is whether a sprinkler is considered to be obstructed. While the premise of the obstruction tables within NFPA 13 is fairly straightforward, there are a handful of variations in the tables that are dependent upon the edition of 13 being used, the sprinkler type, and in some cases the orientation of the sprinkler.

We built a cheatsheet to show all the options for providing code-compliant sprinkler spacing near obstructions. We call is our Obstruction Cheatsheet. Click the button here to download a copy:​

GET THE SPRINKLER OBSTRUCTION CHEATSHEET (PDF)

We also took this a step further, and developed what we call our Ceiling Obstruction Calculator. This reference tool below was built to quickly determine whether a ceiling-mounted element is considered an obstruction. It can be especially helpful during sprinkler layout or during site review where lugging the entire code volume might not be practical.

Common examples of where obstructions are considered are with sprinklers adjacent to surface-mounted lights, soffits (not against a wall), mechanical equipment in walk-in coolers and freezers, signage, banners, lowered ceilings, thresholds above large openings, raised ceiling pockets, or exit lighting.

To use this tool, you can use your downloadable version of the Toolkit, or you can see it online here: Ceiling Obstruction Calculator. If you don't know your activation code, or have trouble installing the downloadable version, go here: www.meyerfire.com/support.

TRY THE CEILING OBSTRUCTION CALCULATOR