Attendance Requirements for Tank Car Unloading

This responds to your letter of June 3, 1999, requesting clarification of the attendance requirements for unloading tank cars under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you ask for clarification as to when the attendance requirements apply and whether the attendance requirements can be met with a remote monitoring system. Please accept my apology for our delay in answering your inquiry.

The tank car unloading attendance requirements are in § 174.67(i) of the HMR. These requirements apply to all tank car unloading operations, including both bottom and top off-loading operations. Section 174.67(i) requires a tank car to be continuously attended throughout the entire period of unloading and while the tank car is connected to an unloading device. This requirement can be met by human attendance or by use of signaling systems, such as sensors, alarms, and electronic surveillance equipment.

Human monitoring must be performed by the person responsible for the unloading operation. The attendant may monitor unloading from on-site or from a remote location within the plant by utilizing television cameras and monitors. In either location, the attendant must have an unobstructed view of the tank car and unloading components. Further, the attendant must be knowledgeable about the product, have the ability to identify conditions requiring action, and have the capability and authority to halt the flow of product immediately.

If a signaling system is used to meet the attendance requirement, the system must provide a surveillance capability at least equal to that of a human observer. The system should be designed to provide immediate notification of a malfunction to a person responsible for unloading; if not, the system must be checked at least once every hour to assure proper functioning. In the event of a system malfunction, human observation of the unloading operation, as described above, must be instituted immediately.

"Transportation," as defined in § 5102 of federal hazardous materials transportation law (49 U.S.C. 5101-5127), means the movement of property and any loading, unloading, or storage incidental to the movement. Neither the statute nor the HMR define the terms "loading incidental to movement," "unloading incidental to movement," or "storage incidental to movement." You are correct that there is confusion concerning the meaning of "transportation in commerce" and whether particular activities are covered by that term and, therefore, subject to regulation under the HMR. We are currently engaged in a rulemaking, under Docket No. RSPA-98-4952, to clarify the applicability of the HMR to specific transportation functions, including hazardous materials loading and unloading operations and storage of hazardous materials during transportation. We expect to issue a notice of proposed rulemaking later this year.