WASHINGTON — The Pipeline and Hazardous Materials Safety Administration has narrowed the list of materials subject to current security plan requirements for the transportation of hazardous materials.

Under the final rule, effective Oct. 1, 2010, certain types and quantities of hazardous materials will no longer be under the regulation.

The PHMSA, an agency of the US DOT,  evaluated transportation scenarios in which a terrorist could use hazardous materials to cause large-scale casualties and property damage. Those materials that are unlikely to be targeted will be removed from the list.

In determining the final list, PHMSA considered physical and chemical properties of the materials and they could contribute, if at all, to a security incident; quantities shipped and mode of transport; past terrorist use; potential use; and availability.

Narrowing the list should reduce regulatory costs and the paperwork involved with compliance, says the agency.

The HMR requires transporters of certain hazardous materials to develop and implement security plans, which include an assessment of possible transportation security risks and appropriate measures to address them.

At a minimum, a carrier’s plan must address personnel security, unauthorized access, and en route security, such as measures to address security risks during transport, including shipments stored temporarily.

"Accordingly, each security plan will differ because it will be based on … a carrier’s individualized assessment of the security risks associated with the specific hazardous materials it ships or transports and its unique circumstances and operational environment."