09 IFC
1504.3 Design and construction. Design and construction of spray rooms, spray booths and spray spaces shall be in accordance with Sections 1504.3 through 1504.3.3.1.
1504.3.1 Spray rooms. Spray rooms shall be constructed and designed in accordance with this section and the International Building Code, and shall comply with Sections 1504.4 through 1504.8.
1504.3.1.1 Floor. Combustible floor construction in spray rooms shall be covered by approved, noncombustible, nonsparking material, except where combustible coverings, including but not limited to thin paper or plastic and strippable coatings, are utilized over noncombustible materials to facilitate cleaning operations in spray rooms.
1504.7 Ventilation. Mechanical ventilation of flammable vapor areas shall be provided in accordance with Section 502.7 of the International Mechanical Code.
1504.7.1 Operation. Mechanical ventilation shall be kept in operation at all times while spraying operations are being conducted and for a sufficient time thereafter to allow vapors from drying coated articles and finishing material residue to be exhausted. Spraying equipment shall be interlocked with the ventilation of the flammable vapor areas such that spraying operations cannot be conducted unless the ventilation system is in operation.
1504.7.2 Recirculation. Air exhausted from spraying operations shall not be recirculated.
Exceptions:
1. Air exhausted from spraying operations is allowed to be recirculated as makeup air for unmanned spray operations, provided that:
1.1. The solid particulate has been removed.
1.2. The vapor concentration is less than 25 percent of the LFL.
1.3. Approved equipment is used to monitor the vapor concentration.
1.4. When the vapor concentration exceeds 25 percent of the LFL, the following shall occur:
a. An alarm shall sound; and
b. Spray operations shall automatically shut down.
1.5. In the event of shutdown of the vapor concentration monitor, 100 percent of the air volume specified in Section 510 of the International Mechanical Code is automatically exhausted.
2. Air exhausted from spraying operations is allowed to be recirculated as makeup air to manned spraying operations where all of the conditions provided in Exception 1 are included in the installation and documents have been prepared to show that the installation does not pose a life safety hazard to personnel inside the spray booth, spraying space or spray room.
1504.7.3 Air velocity. Ventilation systems shall be designed, installed and maintained such that the average air velocity over the open face of the booth, or booth cross section in the direction of airflow during spraying operations, shall not be less than 100 feet per minute (0.51 m/s).
1504.7.4 Ventilation obstruction. Articles being sprayed shall be positioned in a manner that does not obstruct collection of overspray.
1504.7.5 Independent ducts. Each spray booth and spray room shall have an independent exhaust duct system discharging to the outside.
Exceptions:
1. Multiple spray booths having a combined frontal area of 18 square feet (1.67 m2) or less are allowed to have a common exhaust when identical spray finishing material is used in each booth. If more than one fan serves one booth, fans shall be interconnected such that all fans will operate simultaneously.
2. Where treatment of exhaust is necessary for air pollution control or for energy conservation, ducts shall be allowed to be manifolded if all of the following conditions are met:
2.1. The sprayed materials used are compatible and will not react or cause ignition of the residue in the ducts.
2.2. Nitrocellulose-based finishing material shall not be used.
2.3. A filtering system shall be provided to reduce the amount of overspray carried into the duct manifold.
2.4. Automatic sprinkler protection shall be provided at the junction of each booth exhaust with the manifold, in addition to the protection required by this chapter.
1504.7.6 Termination point. The termination point for exhaust ducts discharging to the atmosphere shall not be less than the following distances:
1. Ducts conveying explosive or flammable vapors, fumes or dusts: 30 feet (9144 mm) from the property line; 10 feet (3048 mm) from openings into the building; 6 feet (1829 mm) from exterior walls and roofs; 30 feet (9144 mm) from combustible walls or openings into the building that are in the direction of the exhaust discharge; 10 feet (3048 mm) above adjoining grade.
2. Other product-conveying outlets: 10 feet (3048 mm) from the property line; 3 feet (914 mm) from exterior walls and roofs; 10 feet (3048 mm) from openings into the building; 10 feet (3048 mm) above adjoining grade.
1504.7.7 Fan motors and belts. Electric motors driving exhaust fans shall not be placed inside booths or ducts. Fan rotating elements shall be nonferrous or nonsparking or the casing shall consist of, or be lined with, such material. Belts shall not enter the duct or booth unless the belt and pulley within the duct are tightly enclosed.