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 1525, July 5, 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]
910.3.2.1
Gravity-operated drop-out
				vents.
Automatic smoke and heat vents containing heat-sensitive glazing
				designed to shrink and drop out of the vent opening when exposed to fire shall
				fully open within 5 minutes after the vent cavity is exposed to a simulated
				fire, represented by a time-temperature gradient that reaches an air
				temperature of 500°F (260°C) within 5 minutes. [F]
910.3.2.2
Sprinklered buildings.
Where installed in buildings provided with an
approved
automatic sprinkler system
, smoke and heat vents shall be
				designed to operate automatically. [F]
910.3.2.3
Nonsprinklered
				buildings.
Where installed in buildings not provided with an
approved
automatic sprinkler system
, smoke
				and heat vents shall operate automatically by actuation of a heat-responsive
				device rated at between 100°F (38°C) and 220°F (104°C) above
				ambient. [F]
Exception:
Gravity-operated drop-out vents
				  complying with Section 910.3.2.1.