2003 APRIL - Laserfiche WebLink

20.24.240 single tank or cylinder of gas which pres- ents 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 sec- tion. If a total containment system is uti- lized, the system shall be designed to han- dle 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: [ii] When more than one gas may be emit- ted 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 system shall be sized to process the worst case release of each gas based on the maxi- mum 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. [i] Operated at negative pressure in relation to the surrounding area. [ii] Provided with self-closing limited ac- cess 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 200 feet per minute (fpm) with a minimum of 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 12-gauge. (3) Treatment systems. [i] Treatment systems shall be utilized to process all exhaust ventilation to be dis- charged from gas cabinets, exhausted en- closures or separate storage rooms. Treat- ment systems shall be designed to reduce the maximum allowable discharge concen- tration of the gas to one-half IDLH at the point of discharge to the atmosphere as specified in subsections (e)5 and 6 below. (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 provid- ed, the maximum flow rate of release for the valve or fitting with the highest flow rate shall be indicated. If liquefied gasses are in contact with any valve or fitting, the liquid flow rate shall be utilized for pur- poses of computation of the maximum flow rate of release. All flow rates 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: Container Non liquefied Liquefied Minutes Minutes Cylinders 5 30 Portable Tanks 40 240 710-61 (Pleasanton April 2003)