Code of Massachusetts Regulations
780 CMR - STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
Chapter 9 - Fire Protection Systems
Section 910 - SMOKE AND HEAT VENTS
Subsection 910.3 - Design and installation
Current through Register 1531, September 27, 2024
The design and installation of smoke and heat vents and draft curtains shall be as specified in Sections 910.3.1 through 910.3.5.2 and Table 910.3. [F]
TABLE 910.3 REQUIREMENTS FOR DRAFT CURTAINS AND SMOKE AND HEAT VENTSa [F]
| OCCUPANCY GROUP AND COMMODITY CLASSIFICATION | DESIGNATED STORAGE HEIGHT (feet) | MINIMUM DRAFT CURTAIN DEPTH
(feet) |
MAXIMUM AREA FORMED BY DRAFT CURTAINS
(square feet) |
VENT-AREA-
TO-FLOOR-AREA RATIOc |
MAXIMUM
SPACING OF VENT CENTERS (feet) |
MAXIMUM DISTANCE FROM VENTS TO WALL OR DRAFT
CURTAINb
(feet) |
| Group F-1 and S-1 | - | 0.2 * Hd but >_= 4 |
50,000 | 1:100 | 120 | 60 |
| High-piled Storage (see Section 910.2.2) Class I-IV commodities (Option 1) |
<= 20 | 6 | 10,000 | 1:100 | 100 | 60 |
| >20 <= 40 | 6 | 8,000 | 1:75 | 100 | 55 | |
| High-piled Storage (see Section 910.2.2) Class I-IV commodities (Option 2) |
<= 20 | 4 | 3,000 | 1:75 | 100 | 55 |
| >20 <= 40 | 4 | 3,000 | 1:50 | 100 | 50 | |
| High-piled Storage (see Section 910.2.2) High-hazard commodities (Option 1) |
<= 20 | 6 | 6,000 | 1:50 | 100 | 50 |
| > 20 <= 30 | 6 | 6,000 | 1:40 | 90 | 45 | |
| High-piled Storage (see Section 910.2.2) High-hazard commodities (Option 2) |
<= 20 | 4 | 4,000 | 1:50 | 100 | 50 |
| > 20 <= 30 | 4 | 2,000 | 1:30 | 75 | 40 |
| For SI: 1 foot = 304.8 mm, 1 square foot = 0.0929 m2.
a. Additional requirements for rack storage heights in excess of those indicated shall be in accordance with Chapter 23 of the International Fire Code. For solid-piled storage heights in excess of those indicated, an approved engineered design shall be used. b. Vents adjacent to walls or draft curtains shall be located within a horizontal distance not greater than the maximum distance specified in this column as measured perpendicular to the wall or draft curtain that forms the perimeter of the draft curtained area. c. Where draft curtains are not required, the vent area to floor area ratio shall be calculated based on a minimum draft curtain depth of 6 feet (Option 1). d. "H" is the height of the vent, in feet, above the floor. |
910.3.1 Design. Smoke and heat vents shall be listed and labeled to indicate compliance with UL 793. [F]
910.3.2 Vent operation. Smoke and heat vents shall be capable of being operated by approved automatic and manual means. Automatic operation of smoke and heat vents shall conform to the provisions of Sections 910.3.2.1 through 910.3.2.3. [F]
Exception: Gravity-operated drop-out vents complying with Section 910.3.2.1.
910.3.3 Vent dimensions. The effective venting area shall not be less than 16 square feet (1.5 m2) with no dimension less than 4 feet (1219 mm), excluding ribs or gutters having a total width not exceeding 6 inches (152 mm). [F]
910.3.4 Vent locations. Smoke and heat vents shall be located 20 feet (6096 mm) or more from adjacent lot lines and fire walls and 10 feet (3048 mm) or more from fire barriers. Vents shall be uniformly located within the roof in the areas of the building where the vents are required to be installed by Section 910.2 with consideration given to roof pitch, draft curtain location, sprinkler location and structural members. [F]
910.3.5 Draft curtains. Where required by Table 910.3, draft curtains shall be installed on the underside of the roof in accordance with this section. [F]
Exception: Where areas of buildings are equipped with ESFR sprinklers, draft curtains shall not be provided within these areas. Draft curtains shall only be provided at the separation between the ESFR sprinklers and the non-ESFR sprinklers.
