Section 453 Group L [SFM]
The gross square footage of an individual laboratory suite shall not exceed 10,000 sq ft (929 m2).
- The floor construction of the laboratory suite and the construction supporting the floor of the laboratory suite are allowed to be 1-hour fire-resistance rated in buildings of Type IIA, IIIA and VA construction.
- When an individual laboratory suite occupies more than one story, the intermediate floors contained within the suite shall comply with the requirements of Table 601.
Any story containing a Group L occupancy above the 10th story shall be subdivided by a fire-smoke barrier constructed as a fire barrier having a fire resistance rating of not less than 2-hours and shall also comply with the smoke barrier requirements of Section 709.
A minimum of one door opening shall be provided in the 2-hour fire-smoke barrier for emergency access.
An area for emergency response equipment shall be provided on each floor in an approved location. The area shall be a minimum of 50 square feet (4.6 m2), accessed from outside the laboratory suite and identified with signage
Emergency power shall be provided for all electrically operated equipment, systems and connected control circuits including:
- Mechanical ventilation systems. See Section 4184.108.40.206.
- Emergency alarm and monitoring systems.
- Temperature control systems required to prevent unsafe process excursions or chemical reactions.
- Treatment systems and scrubbers.
- Egress lighting.
- Electrically operated systems required elsewhere in this code and the California Fire Code.
Fire dampers, smoke dampers or fire/smoke dampers shall not be permitted in product conveying and other mechanical exhaust duct systems used to maintain a safe laboratory environment. When the exhaust duct penetrates the laboratory suite boundary the exhaust duct shall be located within a horizontal assembly having a fire resistance rating equal to the fire barrier.
Laboratory suite exhaust air shall be independently ducted to a point outside the building or a roof top structure.
- Exhaust ducts serving a single laboratory suite.
- Exhaust ducts serving separate laboratory suites on the same story may be connected to a common duct within a fire rated vertical shaft when the sub-duct extends vertically upward at least 22 inches.
- Exhaust ducts serving separate laboratory suites on the basement through the 4th story may be connected to a common duct within a fire rated vertical shaft when the sub-duct extends vertically upward at least 22 inches.
- Exhaust ducts serving separate laboratory suites on the 5th story and above may be connected to a common duct that does not exceed 100 vertical feet within a fire rated vertical shaft when the subducts extends vertically upward at least 22 inches. Ducts serving the 5th story and above shall be separate from the duct serving the 4th story and below, but may be within the same fire rated shaft.
When operating on emergency power, the ventilation rate may be reduced to a level sufficient to maintain a differential pressure negative to the surrounding area.
Mechanical ventilation systems shall be designed and balanced such that during normal and emergency conditions the door opening forces comply with the requirements of Sections 1008.1.3 and Chapter 11B as applicable. Emergency conditions shall include: supply fan shutdown or failure, closing of smoke dampers or combination fire/smoke dampers, or emergency power.
The enforcing agency may require a technical opinion and report to identify and develop methods of protection from the hazards presented by the hazardous materials. A qualified person, firm or corporation, approved by the enforcing agency, shall prepare the opinion and report, and shall be provided without charge to the enforcing agency. The opinion and report may include, but is not limited to, the preparation of a hazardous material management plan (HMMP); chemical analysis; recommendations for methods of isolation, separation, containment or protection of hazardous materials or processes, including appropriate engineering controls to be applied; the extent of changes in the hazardous behavior to be anticipated under conditions of exposure to fire or from hazard control procedures; and the limitations or conditions of use necessary to achieve and maintain control of the hazardous materials or operations. The report shall be entered into the files of the code enforcement agencies. Proprietary and trade secret information shall be protected under the laws of the state or jurisdiction having authority.
When a hazardous material has multiple hazards, all hazards shall be addressed and controlled in accordance with the provisions of this code.
|STORY||PERCENTAGE OF MAXIMUM ALLOWABLE QUANTITY PER LABORATORY SUITEa, b||NUMBER OF LAB SUITES PER FLOOR BASED ON CONSTRUCTION TYPE|
|Type IA||Type IB||Type IIA, IIIA, IV||Type IIB, IIIB, VA||Type VB|
|Above grade plane||Above 20||0||NP||NP||NP||NP||NP|
|15 to 20||25||4||NP||NP||NP||NP|
|11, 12, 13, 14||50||8||NP||NP||NP||NP|
|7, 8, 9, 10||50||16||NP||NP||NP||NP|
|Below grade plane||1||75c||10||10||10||10||10|
|3 and below||0||NP||NP||NP||NP||NP|
- Percentages shall be of the maximum allowable quantity per laboratory suite shown in Tables 307.1(1) and 307.1(2). Allowable hazardous material increases for buildings equipped throughout with an automatic sprinkler system shall not be applicable to Group L occupancies.
- When an individual laboratory suite occupies more than one story, the more restrictive percentage of the maximum allowable quantity per laboratory suite shall apply.
- The total aggregate quantity of flammable liquids on the first story below grade shall be limited to the maximum total aggregate quantity for Group B occupancy control areas.
- The total aggregate quantity of flammable liquids on the second story level below grade shall be limited to a maximum total aggregate quantity for Group B occupancy control areas.
Transportation of hazardous materials above the 10th story shall be limited to 5 percent of the maximum allowable quantities of Tables 307.1 (1) and 307.1(2.) Quantities are permitted to be increased 100 percent in buildings with an approved automatic sprinkler system in accordance with Section 903.3.1.1. Materials where footnote g of Table 307.1(1) applies shall not be increased.