Division 4 — SPECIFIC PROVISIONS

(a)

General.

(1)

The specific provisions required by this article shall be in addition to those requirements specified in the fire code. The requirements for the use or indoor storage of regulated materials shall be cumulative as the hazard class of regulated material increases, in accordance with the following table:

Hazard Classifications and Controls

(2)

Exterior storage of regulated materials is covered by subsection (f) of this section.

(3)

All control equipment for materials regulated by this article shall meet appropriate nationally recognized standards, if any, approved by the Fire Chief.

(b)

Class I controls. Persons responsible for any facility where Class I materials are present shall comply with all of the requirements of this subsection (b) and with subsections (c), (d), (e), and (f) of this section.

(1)

Piping.

(i)

Piping for Class I materials shall be designed and fabricated from materials compatible with the material to be contained. Piping shall be of strength and durability sufficient to withstand the pressure, structural, and seismic stress and exposure to which it may be subjected, as required by the Uniform Building Code.

(ii)

Secondary containment shall be provided for piping for Class I materials. The secondary containment shall be capable of directing a sudden release into an approved discharge treatment system, and shall be monitored continually with a continuous gas monitoring system approved by the Fire Chief. Secondary containment includes, but is not limited to, double walled piping.

(2)

Automatic shut-off. An automatic shut-off valve which is of a "fail-safe to close" design shall be provided. Each of the following shall activate automatic shut-off:

(i)

Gas detection.

(ii)

Manually, from remote locations.

(iii)

Failure of emergency power.

(iv)

Seismic activity, upon a seismic event within five (5) seconds of horizontal semisoidal oscillation having a peak acceleration of .3g (=2.94m/sec 2 ) and a period of .4 seconds.

(v)

Failure of primary containment.

(vi)

Activation of manual fire alarm.

(3)

Emergency control station. Signals from emergency equipment shall be transmitted to an emergency control station which is continually staffed by trained personnel.

(c)

Class II controls. Responsible persons shall cause materials which are classified as Class II materials to be provided with the controls specified in this subsection (c) and in subsections (d), (e) and (f) of this section.

(1)

Connections.

(i)

Piping and tubing shall be installed in accordance with appropriate nationally recognized standards, if any, approved by the Fire Chief, and shall have welded connections compatible with the regulated material throughout unless an exhausted enclosure is provided.

(ii)

Material which is not compatible with ferrous piping may be installed in nonferrous piping approved by the Fire Chief.

(iii)

Where connections other than welded connections meet appropriate nationally recognized industry standards, if any, a person responsible for a facility may seek an exception from the Fire Chief, by filing a request for exception with the Fire Chief, which shall document the standards and reason for the exception.

(2)

Local gas shutoff.

(i)

Manual activation controls shall be provided at locations near the point of use and near the source, as approved by the Fire Chief.

(ii)

The Fire Chief may require additional controls at other places, including, but not limited to, the entry to the building, the area in the building where regulated materials are stored or used, and emergency control stations.

(iii)

Manually activated shutoff valves shall be of "fail-safe to close" design.

(3)

Emergency power. Emergency power shall be provided for:

(i)

Exhaust ventilation, including the power supply for treatment systems.

(ii)

Gas-detection systems.

(iii)

Emergency alarm systems.

(iv)

Temperature-control systems which comply with the fire code.

(4)

Excess flow control.

(i)

Portable tanks and cylinders shall be provided with excess flow control.

(ii)

Valves shall be permanently marked to indicate the maximum design flow rate.

(5)

Gas detection. A continuous gas-detection system in accordance with Chapters 6 and 9 shall be provided to detect the presence of gas at or below the permissible exposure limit. The detection system shall initiate a local alarm and transmit a signal to a continually staffed remote location to provide an immediate response to an alarm. The alarm shall be both visual and audible and shall be designed to provide warning both inside and outside of the storage, use or handling area. The audible alarm shall be distinct from all other on-site alarms.

(6)

Reduced flow valves. Reduced flow valves may be utilized to reduce the maximum flow rate from cylinders and tanks under full flow conditions. Valve flow rates may be considered in determining the size of treatment systems required for a worst case release.

(7)

Seismic shut-off valves. A seismically activated valve meeting standards approved by the Fire Chief shall be provided for automatic shut-off of regulated materials upon a seismic event within five (5) seconds of horizontal semisoidal oscillation having a peak acceleration of .3g (= 2.94m/sec 2 ) and a period of .4 seconds.

(8)

Class II corrosives. Inert construction materials shall be used for the primary containment of Class II regulated materials which are corrosives. Alternatively, secondary containment shall be provided for Class II materials which are corrosives.

(9)

Emergency alarms. When materials regulated by this article are transported through exit corridors or exit enclosures, there shall be an emergency telephone system or a local manual alarm station or a signaling device approved by the Fire Chief at not more than one hundred fifty-foot intervals and at each exit doorway throughout the transport route. The signal shall be relayed to an approved central, proprietary or remote station service or a constantly attended on-site location and shall also initiate a local audible alarm.

(d)

Class III controls. Persons responsible for a facility shall cause materials which are classified as Class III materials to be provided with the controls specified in this subsection (d) and in subsections (e) and (f) of this section.

(1)

Piping, valves, and fittings.

(i)

Piping, valves, fittings and related components shall be designed and fabricated from materials compatible with the material to be contained. They shall have strength and durability sufficient to withstand the pressure, structural and seismic, and any other stress and exposure to which they may be subjected.

(ii)

Expansion chambers shall be provided between valves whenever the regulated gas may be subjected to thermal expansion. Chambers shall be sized to provide protection for piping, valves and instrumentation and to accommodate the expansion of regulated materials.

(2)

Signage.

(i)

Stationary aboveground tanks shall be placarded with hazard identification signs as specified in the fire code for the specific material contained.

(ii)

Signs prohibiting smoking shall be posted in indoor storage, use and handling areas and within twenty-five (25) feet of outdoor storage, use and handling areas.

(iii)

Signs shall not be obscured or removed.

(iv)

Signs shall be in English and such other languages as may be appropriate, as determined by the Fire Chief.

(v)

Signs shall be durable.

(vi)

The size, color and lettering shall be in conformance with nationally recognized standards determined by the Fire Chief to be applicable to the regulated material.

(3)

Inert gas purge system. Gas systems for regulated materials shall be provided with individually dedicated inert gas purge systems (e.g., nitrogen, helium, argon and neon).

(e)

Minimum threshold quantity controls. Responsible persons shall cause materials which do not exceed the minimum threshold quantity to be provided with the controls specified in this subsection (e) and in subsection (f) of this section.

(1)

Exhaust ventilation.

(i)

Storage of cylinders shall be within ventilated gas cabinets, exhausted enclosures or within a ventilated separate gas storage room as defined in the fire code.

(ii)

Storage of portable and stationary tanks shall be within a separate ventilated room without other occupancy or use.

(iii)

If gas cabinets are provided, the room or area in which they are located shall have independent exhaust ventilation.

(iv)

Exhaust systems for gas cabinets, exhausted enclosures and separate gas storage rooms shall be designed to handle the accidental release of gas. Such exhaust systems shall be capable of diluting,

absorbing, neutralizing, burning or otherwise processing the entire contents of the single tank or cylinder of gas which presents the highest potential hazard.

(v)

Systems utilized for such processing shall be designed as a treatment system, as described in subsection (e)3 of this section. If a total containment system is utilized, the system shall be designed to handle the maximum anticipated pressure of release to the system when the system reaches equilibrium.

(2)

Gas cabinets. When gas cabinets are provided they shall be:

(i)

Operated at negative pressure in relation to the surrounding area.

(ii)

Provided with self-closing limited access ports or fire-rated windows to give access to equipment controls. The average velocity of ventilation at the face of access ports or windows shall be not less than two hundred (200) feet per minute (fpm) with a minimum of one hundred fifty (150) fpm at any other point of the access port or window.

(iii)

Connected to a treatment system.

(iv)

Provided with self-closing doors.

(v)

Constructed of steel with a thickness not less than twelve (12) gauge.

(3)

Treatment systems.

(i)

Treatment systems shall be utilized to process all exhaust ventilation to be discharged from gas cabinets, exhausted enclosures or separate storage rooms. Treatment systems shall be designed to reduce the maximum allowable discharge concentration of the gas to one-half IDLH at the point of discharge to the atmosphere as specified in subsections (e)(5) and (6) below.

(ii)

When more than one (1) gas may be emitted to the treatment system, the treatment system shall be designed to handle the worst case release based on the release rate, the quantity and the IDLH for all the

gases stored or used.

(4)

Treatment system sizing. Treatment systems shall be sized to process the worst case release of each gas based on the maximum flow rate of release from the cylinder or tank utilized which presents the highest potential hazard. The entire contents of tanks and cylinders shall be considered.

(5)

Stationary tanks.

(i)

Stationary tanks shall be labeled with the maximum rate of release for the gas contained based on any valves or fittings that are inserted directly into the tank.

(ii)

If multiple valves or fittings are provided, the maximum flow rate of release for the valve or fitting with the highest flow rate shall be indicated. If liquefied gases are in contact with any valve or fitting, the liquid flow rate shall be utilized for purposes of computation of the maximum flow rate of release. All flow rate indicated on the label shall be converted to cubic feet per minute of gas at normal temperature and pressure.

(6)

Portable tanks and cylinders.

(i)

For portable tanks and cylinders, the maximum flow rate of release shall be calculated based on assuming the total release from the cylinder or tank within the time specified in the table below:

(ii)

When portable tanks or cylinders are equipped with approved reduced flow valves, the worst case release will be determined by the maximum achievable flow from the valve as determined by the valve manufacturer or the gas supplier. Reduced flow and excess flow valves shall be permanently marked to indicate the maximum design flow rate. Such markings shall indicate the flow rate for air under standard conditions.

(7)

Gas detection for D.O.T. Poison A. A portable or fixed gas detection system capable of monitoring at PEL for each regulated material classified as a D.O.T. Poison A stored or used within the facility shall be provided.

(f)

Exterior storage.

(1)

General. Persons responsible for a facility where there is exterior storage of any regulated material shall comply with the provisions of this subsection (f) and the Uniform Building Code.

(2)

Distance limitation to exposures. Exterior storage of regulated materials shall not be within seventy-five (75) feet of a building, structure, property line, street, alley, public way or exit to a public way unless the storage is shielded by a structure which has a minimum fire resistive rating of two (2) hours and which interrupts the line of sight between the storage and the exposure. The shielding structure shall be at least five (5) feet from any exposure. The shielding structure shall have not more than two (2) sides which shall be at approximately ninety-degree directions.

(3)

Openings in buildings subject to exposure. When an exterior storage area is located within seventy-five (7.5) feet of a building, openings into the building other than piping shall not be above the height of the top of the shielding structure referred to in subsection (f)(2) of this section or within fifty (50) feet horizontally from the storage area, whether or not protected by a shielding structure.

(4)

Air intakes. No exterior storage area for regulated materials shall be within seventy-five (75) feet of any air intake.

(5)

Canopies. Portable tanks and cylinders stored outside of buildings shall be stored under a canopy constructed of noncombustible materials. Such exterior storage shall not be considered indoor storage. An automatic fire-sprinkler system, or alternative systems as determined by the Fire Chief for materials incompatible with water, shall be provided for canopies installed for the storage of regulated materials.

(6)

Stationary tank controls. Controls on stationary tanks shall be in accordance with the following:

(i)

Pressure-relief devices shall be vented to a treatment system designed in accordance with the provisions of subsection (e)(3) of this section.

(ii)

Where filling or dispensing connections are provided, they shall be provided with a means of local exhaust. Such exhaust shall be designed to capture fumes and vapors. The exhaust shall be directed to a treatment system designed in accordance with the provisions of subsection (e)(3) of this section.

(iii)

Stationary tanks shall be provided with a means of excess flow control on all tank inlet or outlet connections. Inlet connections that are designed to preclude backflow and pressure-relief devices are exempt from this requirement.

(7)

Gas cabinets for leaking cylinders.

(i)

At least one (1) gas cabinet or exhausted enclosure shall be provided for the handling of leaking cylinders. The cabinet or enclosure shall be within or adjacent to the exterior storage area and connected to a treatment system as specified in subsection (e)(3) of this section.

(ii)

A gas cabinet or exhausted enclosure need not be provided for leaking cylinders if all cylinders are stored within gas cabinets or exhausted enclosures.

(8)

Local exhaust for leaking portable tanks.

(i)

A means of local exhaust shall be provided to capture regulated material leaking from portable tanks. The local exhaust may consist of portable ducts or collection systems designed to be applied to the site of a leak in a valve or fitting on the tank. The local exhaust system shall be connected to a treatment system as specified in subsection (e)3 of this section.

(ii)

A local exhaust system shall be provided within or immediately adjacent to every exterior storage area; and within separate gas storage rooms used for portable or stationary tanks.

(g)

Tank cars and piping.

(1)

The provisions of this article shall not apply to tank cars which meet all requirements of the U.S. Department of Transportation, while such tank cars are used for the transportation and unloading of regulated material, as such terms are used in the Hazardous Materials Transportation Act, 49 U.S.C. § 1801 et seq. "Unloading" does not include the use of tank cars to store regulated materials.

(2)

The provisions of this article shall apply to piping and control systems, automatic shut-off valves, emergency control stations, gas detection systems, treatment systems and alarm systems used with piping which connect tank cars to facilities for the unloading and delivery of regulated material, and to tank cars used to store regulated materials.

(Ord. No. 2017, § IV, 8-5-96)