SEC. 91.7105. EXISTING BUILDINGS.

   Additions, alterations, repairs, changes of use or changes of occupancy to existing buildings shall comply with the methane mitigation requirements of LAMC Subsections 91.7104.1 and 91.7104.2, when required by Divisions 81 or 82 of Article 1, Chapter IX of the LAMC. (Amended by Ord. No. 184,692, Eff. 12/30/16.)

   Approved methane mitigation systems in existing buildings shall be maintained in accordance with LAMC Section 91.7106. (Amended by Ord. No. 185,587, Eff. 7/16/18.)

SEC. 91.7106. TESTING, MAINTENANCE AND SERVICE OF GAS-DETECTION AND MECHANICAL VENTILATION SYSTEMS.

   (Amended by Ord. No. 185,587, Eff. 7/16/18.)

   The installation instructions for the gas detection and mechanical ventilation systems, which are required by LAMC Table 71, shall be approved and enforced by the Fire Department. All gas detection and mechanical ventilation systems shall be maintained and serviced in proper working condition and meet all requirements of the State of California and City Electrical and Mechanical Codes.

   A.   Fire Department. The Fire Department shall enforce the following:

   1.   The maintenance and service procedures for each gas detection and mechanical ventilation systems, which are required in LAMC Table 71, shall be performed by the building owner in accordance with the manufacturers written instructions.

   2.   The annual and maintenance testing shall be performed as set forth by the Fire Department in accordance with the Fire Prevention Bureau (F.P.B.) Requirement No. 71 and Fire Chief's Regulation 4, Section 4J.

   3.   The testing of the gas detection and mechanical ventilation systems shall be performed by a person with a valid Certificate of Fitness for Gas Detection Systems as set forth in LAMC Section 57.117.

   B.   Notification Placard. A permanent notification placard shall be posted and maintained at the front entrance of a building that is constructed with Impervious Membrane, except in residential buildings. The placard shall indicate the presence of the Impervious Membrane.

SEC. 91.7107. EMERGENCY PROCEDURES.

   With the exception of single-family dwellings, all buildings required by this division to have a gas detection system or sub-slab vent system shall, subject to Fire Department approval, have established emergency procedures that include, but are not limited to, the following: (Amended by Ord. No. 180,619, Eff. 5/12/09.)

   A.   Assignment of a responsible person as safety director to work with the Fire Department in the establishment, implementation and maintenance of an emergency plan.

   B.   Conspicuous posting of the Fire Department’s telephone number in areas designated by the Fire Department.

   C.   Conspicuous posting of emergency plan procedures approved by the Fire Department.

SEC. 91.7108. APPLICATION OF METHANE SEEPAGE REGULATIONS TO LOCATIONS OR AREAS OUTSIDE THE METHANE ZONE AND METHANE BUFFER ZONE BOUNDARIES.

   (Amended by Ord. No. 185,587, Eff. 7/16/18.)

   Upon a determination by the Department that a hazard may exist from methane intrusion at a geographical location or in an area outside the boundaries established in LAMC Section 91.7103, the Department and the Fire Department may enforce any or all of the requirements of Division 71, Article 1, Chapter IX of the LAMC as required to preclude potential fire or explosion from methane concentration.

SEC. 91.7109. ADDITIONAL REMEDIAL MEASURES.

91.7109.1. General Remedial Measures. In the event the concentration of methane gas in any building located in a Methane Zone or Methane Buffer Zone reaches or exceeds 25 percent of the minimum concentration of gas that will form an ignitable mixture with air at ambient temperature and pressure, the owner shall hire an engineer to investigate, recommend and implement mitigating measures. These measures shall be subject to approval of this Department and the Fire Department.

91.7109.2. Abandoned Oil Well. (Amended by Ord. No. 185,587, Eff. 7/16/18.) Any abandoned oil well encountered during construction shall be evaluated by the Fire Department and may be required to be re-abandoned in accordance with applicable rules and regulations of the Division of Oil, Gas and Geothermal Resources of the State of California. Buildings shall comply with these provisions and the requirements of LAMC Section 91.6105, whichever is more restrictive.

TABLE 71. MINIMUM METHANE MITIGATION REQUIREMENTS

(Amended by Ord. No. 185,587, Eff. 7/16/18.)

Site Design Level			LEVEL I		LEVEL II		LEVEL III		LEVEL IV		LEVEL V
Design Methane Concentration (ppmv)			0-100		101-1,000		1,001-5,000		5,001-12,500		>12,500
Design Methane Pressure (inches of water pressure)			2	>2	2	>2	2	>2	2	>2	All Pressures
P A S S I V E S Y S T E M	De-watering System 1		X	X	X	X	X	X	X	X	X
	Sub-Slab Vent System	Perforated Horizontal Pipes	X	X	X	X	X	X	X	X	X
		Gravel Blanket Thickness Under Impervious Membrane	2"	2"	2"	3"	2"	3"	2"	4"	4"
		Gravel Thickness Surrounding Perforated Horizontal Pipes	2"	2"	2"	3"	2"	3"	2"	4"	4"
		Vent Risers	X	X	X	X	X	X	X	X	X
	Impervious Membrane		X	X	X	X	X	X	X	X	X
A C T I V E S Y S T E M	Sub-Slab System	Mechanical Extraction System 2								X	X
	Lowest Occupied Space System	Gas Detection System 3		X		X	X	X	X	X	X
		Mechanical Ventilation 3, 4, 5		X		X	X	X	X	X	X
		Alarm System		X		X	X	X	X	X	X
	Control Panel			X		X	X	X	X	X	X
M I S C. S Y S T E M	Trench Dam		X	X	X	X	X	X	X	X	X
	Conduit or Cable Seal Fitting		X	X	X	X	X	X	X	X	X
	Additional Vent Risers 5										X

 

For SI: 1 inch = 25.4 mm.

X = Indicates a Required Mitigation Component

1.   See LAMC Subdivision 91.7104.3.7 for exception.

2.   The Mechanical Extraction System shall be capable of providing an equivalent of a complete change of air every 20 minutes of the total volume of the Gravel Blanket.

3.   The mechanical ventilation systems shall be capable of providing an equivalent of one complete change of the lowest occupied space air every 15 minutes.

4.   Vent opening complying with LAMC Subdivision 91.7104.3.4 may be used in lieu of mechanical ventilation.

5.   The total quantity of installed vent risers shall be increased to double the rate for passive system.

DIVISION 72 FIRE DISTRICT REGULATIONS

(Division 72 Added by Ord. No. 170,953, Eff. 3/17/96, Oper. 1/1/96.)

Section

91.7200   Purpose.

91.7201   General.

91.7202   Additions to Buildings.

91.7203   General Requirements.

91.7204   Special Requirements for Fire District Number 1.

91.7205   Provisional Structures.

91.7207   Special Requirements for the Very High Fire Hazard Severity Zone.

91.7208   Prohibited Vehicles.

SEC. 91.7200. PURPOSE.

   (Amended by Ord. No. 182,850, Eff. 1/3/14.)

   These Fire District Regulations were formerly found in Division 61.