sprinklernotes
Combustible Gravity Chute
The following information was provided: We have a trash chute with sprinklers
installed in the chute intake at the top and every other floor as required. The
AHJ is asking about adding a sprinkler at the top of the chute outside the
building. They claim it is combustible construction and will need a sprinkler.
You asked the following question: Is a sprinkler required at the top of the
trash chute?
In response to your question(s), we have reviewed NFPA 13, Standard for the
Installation of Sprinkler Systems, 2019 edition and NFPA 82, Standard on
Incinerators, and Waste and Linen Handling Systems and Equipment, 2019 edition.
Our informal interpretation: A sprinkler is not required at the top of the
chute outside the building.
The requirements for automatic sprinklers in gravity chutes are found in
Chapter 26 of NFPA 13 which extracts NFPA 82 section 6.2.6:
6.2.6 Automatic Sprinklers.
6.2.6.1 Gravity Chute.
6.2.6.1.1 Gravity chutes shall be protected internally by automatic sprinklers
unless the chute is in accordance with 6.2.2.5 or 6.2.2.6.
6.2.6.1.2 A sprinkler shall be installed at or above the top chute intake of
the chute.
6.2.6.1.3 Automatic sprinklers installed in gravity chute intakes shall be
recessed out of the chute area through which the material travels.
6.2.6.1.4 A sprinkler shall be installed within the chute at alternate floor
levels in chutes connecting more than two stories, with a mandatory sprinkler
located at the lowest service level.
6.2.6.1.5 Sprinkler system installation shall comply with NFPA 13.
Section 6.2.6.1.2 of NFPA 82 requires that a sprinkler be installed above the
highest chute intake. As long as there is a sprinkler installed above that
level, no additional sprinklers are needed any higher. The purpose of the
sprinklers installed at the chute intakes is to prevent a fire in the chute
from migrating into the building. Additionally, Figure A.6.2(b) depicts
sprinklers installed in the chute intakes and no sprinklers installed within
the chute, itself, as required by section 6.2.6.
