188.8.131.52* Manifolding of Exhaust Ducts
Exception No. 1: Multiple cabinet spray booths whose combined frontal area does not exceed 18 ft2 (1.7 m2) shall be permitted to be manifolded if the sprayed materials used will not react and cause ignition of the residue in the ducts.
Exception No. 2: Where treatment of exhaust is necessary for air pollution control or for energy conservation, ducts shall be permitted to be manifolded if all of the following conditions are met:
- The sprayed materials used will not react and cause ignition of the residue in the ducts.
- No finishing materials containing nitrocellose are used.
- An air-cleaning system is provided to reduce the amount of overspray carried into the duct manifold.
- Automatic sprinkler protection is provided at the junction of each booth exhaust with the manifold, in addition to the protection required by 43.1.7.
- The installation is approved by the AHJ. [33:7.6]