Shirlo, Inc. - Executive Summary
Shirlo, Inc. of Memphis, TN is a manufacturer of consumer and chemical-specialty products. A large part of our business includes the blending and packaging of aerosol products. The aerosol packaging processes require Shirlo to maintain a significant inventory of flammable propellants. These propellants are subject to EPA Risk Management Program requirements because they contain Clean Air Act listed chemicals (i.e propane, isobutane, n-butane, dimethyl ether, difluoroethane). These products are stored in two outdoor locations. Six tanks are located south of the manufacturing facility and three are maintained on the northeast side of the property. For the purposes of the RMP, each storage area is considered a seperate process. Shirlo is committed to operating these processes in accordance with federal and consensus regulations in order to protect both employees and the public. |
The six tanks on the south side of the property store flammable propellants which include dimethyl ether
, difluoroethane, and mixtures of propane, isobutane and n-butane. Of these chemicals, dimethyl ether is stored in the largest quantity (72,000 pounds). The dimethyl ether is stored in two interconnected tanks. The three tanks on the northeast side of the property store flammable mixtures of propane, isobutane and n-butane. These tanks are not interconnected, with the largest tank storing a maximum amount of 33,000 pounds of the mixture.
Because the amount of flammable materials in each process exceeds 10,000 pounds, Shirlo has been participating in OSHA Process Safety Management since 1994. These accident prevention activities have included conducting Process Hazard Analysis (PHA), developing operating procedures, conducting maintenance, maintaining an incident investigation program, and conducting compliance audits. With the advent of EPA Risk Management requirements, Shirlo has taken the opportunity to review the Process Safety Management Program to ensure it is compatible
with RMP requirements.
Previous hazard assessment activities for the processes consisted primarily of identifying and abating those hazards posed to onsite employees. As part of our RMP implementation, evaluations were conducted which considered the off-site consequences of chemical release. Both worst-case and alternative-release scenarios were conducted for each process (northeast and south).
The worst-case scenario for the south storage location considered a catastrophic failure of the common pipe from both dimethyl ether tanks, with instantaneous release and vapor cloud explosion of 72,000 pounds of product. As required by RMP, the distance to a 1psi overpressure was calculated. This distance was determined to be 0.3 miles. Within the 0.3 mile radius, there is no residential population. The area in question is solely utilized for industrial and commercial operations. The alternative-release scenario conducted only affected a 0.1 mile radius.
The worst-case release
scenario for the northeast process area considered a release and vapor cloud explosion of the largest tank containing a flammable mixture of propane, isobutane and n-butane. As with the south process, the distance to a 1psi overpressure was found to be 0.3 miles, with the alternative release scenario affecting a 0.1 mile radius.
Shirlo reports to the local emergency planning committee on a yearly basis regarding the chemicals maintained onsite. Additionally, Shirlo has developed an excellent working relationship with the local fire department. Shirlo will rely on the fire department and other local emergency agencies to provide support in the event of a fire or other emerency involving these processes. Shirlo's emergency action plan includes procedures for prompt notification of emergency personnel (fire, police, ems) in the event of a flammable material release.
Shirlo is committed to improving the safety of our process systems. For example, significant improvement to fire sa
fety has been achieved by updating alarm and sprinkler systems in the past six months. Shirlo has not had a single accident with potential offsite consequences involving these processes. We plan to continue making improvements to these systems as long as they are part of our operation.