There is no cut and dry answer as to the maximum amount that you are allowed to store. It depends on many factors including design of the facility, location, state laws, etc. It depends somewhat on the state you are working in.
Here is some general guidance, but you will need to get the state regulations where you are working as well:
Emergency Planning and Community Right-to-Know Act of 1986 (EPCRA)
This federal law is designed to promote emergency planning and preparedness at both the state and local level. It provides citizens, local government, and local response authorities with information regarding the potential hazards in their community. EPCRA requires the use of emergency planning and designates state and local governments as recipients of information regarding certain chemicals used in the community. EPCRA has four major components:
_ Emergency Planning (Sections 301-303)
_ Emergency Release notification (Section 304)
_ Community Right-To-Know reporting (Section 311-312)
_ Toxic Release Inventory reporting (Section 313)
State/Local Regulations
State and local emergency response agencies may establish additional and/or more stringent reporting and planning requirements and may require the use of state-specific reporting forms and fees.
Emergency Planning (EPCRA Section 302 and 303)
A Facility with quantities of Extremely Hazardous Substances (EHS) equal to or greater than the threshold planning quantity (See EPA’s List of Lists) is required to notify your State Emergency Response Commission (SERC) and Local Emergency Planning Committee (LEPC) within 60 days that the facility is subject to emergency planning committee requirements. The facility must designate a representative to participate in the local emergency planning Process as a Facility Emergency Coordinator. The facility must also submit additional information to the LEPC upon request and notify them of any changes at the facility which might be relevant to emergency planning.
There are about 360 specific chemicals classified as EHS including chlorine.
Inventory Reporting (EPCRA Section 312)
A Facility is required by EO 13148 to submit annual chemical inventory forms to the SERC, LEPC, and the Fire Department. The Tier II report or State Form must be submitted on or before March 1 (for the previous calender year) of each year for:
_ All extremely hazardous substances (EHS) present at the facility in amounts equal to or greater than 500 lbs. (227 kg - approximately 55 gallons) or the threshold planning quantity, whichever is lower (See EPA’s List of Lists), and
_ All hazardous chemicals present at the facility at any given time in amounts equal to or greater than 10,000 lbs. (4540 kg).
Examples of Hazardous Chemicals:
Chlorine
If yes, then you have 10,000 lbs. of a hazardous chemicals on-site and must report.
All facilities shall comply with TRI reporting provisions under section 313 of EPCRA, Section 6607 of the Pollution Prevention Act (PPA), all implementing regulations and future amendments of these authorities in light of applicable guidance provided by EPA without regard to Standard Identification Classification (SIC) or North American Industrial Classification System (NAICS) delineations. A facility must also comply with EPCRA section 313 if the total number of work hours at the facility meets or exceeds 20,000 in a year (roughly equal to 10 or more full time employees), and the facility meets or exceeds "manufacture," "process," or otherwise use" thresholds for an EPCRA section 313 (TRI) chemical.
There are more than 600 chemicals and 28 chemical categories covered under EPCRA section 313.
Effective January 1, 2000, EPA created a "new" Persistent Bioaccumulative Toxic classification for 18 chemicals and chemical categories with lower thresholds of 10 pounds and 100 pounds based on their potential to persist and bioaccumulate. A separate threshold for dioxin and dioxin-like compound category was set at 0.1 gram.
The deadline for TRI reporting for calendar year 2000 is July 1, 2001.
For further information regarding the regulations or data requirements:
Note that the OSHA limit listed in this document shows a limit of 1500 lbs onsite before you are subject to the OSHA PSM and 2500 lbs onsite before you are subject to the Part 68 PSM. That would equate to 10-150 lb cylinders.
In general, you would want to keep the chlorine storage volume low so that you can stay away from doing the various risk management plans because updating the risk management plans will be an ongoing expense.
Note that you will still need to check with your state as the state may have more strigent requirements.
There are three fire codes in common use in the US, applicability on which if any of the codes is called for by the state, county, or city.
Uniform Fire Code, National code and Standard Fire Code
All three codes allow the following:
Four 150 # containers of compressed gas are allowed without an exhaust containment system providing the control area has a 1 hour fire wall and sprinklers, and 4 control areas can be located in one building.
The above was an exert from "The Chlorination/ Chloramination Handbook" by G.F. Connell available from the AWWA bookstore and other locations.
