Matheson Gas Products - Twinsburg - Executive Summary |
|
MATHESON GAS PRODUCTS - TWINSBURG, OH BRANCH BACKGROUND This Matheson Gas Products facility transfills and purifies specialty compressed industrial gases in cylinders in both large and small quantities. The source material gas which is transfilled and sometimes purified may be packaged in tube trailers, ton cylinder units or regular cylinders, depending on the gas. The finished product varies from a single pure chemical gas to gas mixtures, and the capacity of product cylinders varies from 2000 pounds to less than 1 pound of gas depending on the size of the cylinder and the type of material involved. Matheson has identified two processes at this site containing greater-than-threshold amounts of chemicals subject to the RMP regulations: hydrogen chloride storage and hydrogen fluoride storage. We have considered storage as an RMP "process". Because of the quantities involved, both processes were assigned to Program 3. We believe a large gas release from this facility is extre mely unlikely. This facility has the equipment, the procedures and the training to ensure that a gas release impacting off-site areas will not occur. They are described in the Prevention Program section of this Executive Summary. DESCRIPTION OF WORST-CASE AND ALTERNATIVE CASE SCENARIOS Worst-Case Scenario In compliance with the USEPA definition of a worst-case scenario, the loss of the entire contents of the largest container over a period of ten minutes was modeled using RMPComp. Such a release is extremely unlikely since 1) it assumes catastrophic failure of a cylinder that is built to withstand pressure and temperature well above normal operating conditions; 2) it assumes the simultaneous failure of all safeguards; and 3) no allowance is made for the presence and use of active mitigation systems and procedures. Consequently this should not be considered a credible release situation. The worst-case release scenario is for hydrogen fluoride and assumes the loss of the la rgest container or 100 lbs. of gas in ten minutes. This represents a release rate of 10 lbs. of gas per minute. The theoretical area of concern to the endpoint is 0.4 miles. Alternative case scenarios For both hydrogen chloride storage and hydrogen fluoride storage the alternative release scenario is a valve leak. There is no real process occurring in storage; and the valve represents the only possible weak point of the cylinder in storage. For hydrogen fluoride storage, the alternative case release assumes a leak rate of .17 lbs./minute or a loss of 100 lbs. over 600 minutes resulting in a theoretical off-site impact of 0.1 miles. For hydrogen chloride storage, the alternative case release assumes a leak rate of .08 lbs./minute or a loss of 60 lbs. over 720 minutes resulting in a theoretical off-site impact of less than 0.1 miles. ACCIDENT HISTORY There have been no accidents in the last five years at this site involving releases of gas from RMP regulated processes. PREVENT ION PROGRAM and EMERGENCY RESPONSE There are numerous safeguards at this facility. First and foremost is the construction of the cylinders themselves. The Department of Transportation (DOT) regulations, the National Fire Protection Association (NFPA) Codes and the Compressed Gas Association (CGA) guidelines mandate the way in which cylinders are manufactured and used. These standards were developed in order to virtually guarantee that cylinders would not fail even under extreme conditions during the rigors of shipping and use. Everything about cylinder construction is mandated, from the type of metallurgy to the wall thickness; every cylinder is designed to withstand a given pressure which must exceed the fill pressure by a certain percentage. Every cylinder is designed to withstand extremes of operation and overpressure conditions that make either catastrophic or routine failure extremely unlikely; and each cylinder must be re-qualified to this standard every five years. In addit ion as with the cylinders themselves, any appurtenance such as pressure relief devices and valves must also meet similarly strict manufacturing standards which are so detailed that they mandate even the number and type of threads on the valve. This facility is also equipped with mitigation equipment if a leak should occur. There are appropriate scrubbers to neutralize any fugitive emissions, and special emergency containment vessels and devices to completely contain a leak. Last but not least there are procedures in place at this facility to ensure leaks do not occur, or to mitigate a leak if it does occur. Cylinders are leak checked when they are first received and leak checked prior to being shipped out. Cylinder areas are routinely inspected. There are trained, experienced operators who have the required knowledge, skills and abilities to safely carry out their responsibilities and are able to assess and resolve possible problems before they result in a release. The Emergen cy Response Plan at this facility includes notification of local agencies and medical providers. Employees have been trained and drilled in emergency response. There is an Emergency Response Team on site that has been trained in accordance with OSHA 29 CFR 1910.120 (Q)(6)(iii). They have access to the necessary equipment to quickly respond to an emergency release. |