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Rail Safety Advisory Letter – 15/13

Operating lever design for tank car bottom outlet valve

Place du Centre
4th Floor
200 Promenade du Portage
Gatineau, Quebec
K1A 1K8


26 November 2013

Ms. Marie-France Dagenais (ASD)
Director General, Transportation of Dangerous Goods
Transport Canada
330 Sparks Street
Ottawa, Ontario
K1A 0N5

Dear Ms. Dagenais:

Operating Lever Design for Tank Car Bottom Outlet Valve

On 03 April 2013, Canadian Pacific Railway (CP) freight train 420-02 (the train) was proceeding eastward on the CP Heron Bay Subdivision. The train was equipped with 3 head-end locomotives and was hauling 111 cars (64 empties and 47 loads), 22 of which were loaded with dangerous goods (DG). The train weighed 8232 tons and was 8198 feet long. At about 0750 Eastern Daylight Time, while travelling at 45 mph, the train experienced an undesired emergency brake application and came to a stop near Bremner, Ontario (Mile 13.1). Subsequent inspection determined that 23 cars (19 loads and 4 empties) had derailed, 8 of which were DG tank cars loaded with petroleum crude oil (UN 1267) (TSB Occurrence No. R13T0060).

During the derailment, a number of the cars slid down an embankment and came to rest in various positions. As a result of the accident, DOT Class 111 non-pressure tank cars TILX 192186, TILX 198203 and PROX 76346 were leaking product. TILX 198203 and TILX 192186 released about 3,220 litres and 98,480 litres of petroleum crude oil respectively. PROX 76346 released about 18,190 litres of canola oil.

During site examination, it was determined that:

The Association of American Railroads (AAR) Manual of Standards and Recommended Practices (MSRP) specification M-1002 (M-1002) governs tank car construction. M-1002 Appendix E, section specifies that bottom outlet valve handles, unless stowed separately, must either be designed to bend or break free on impact or be positioned so that the handles, in the closed position, are above the bottom surface of the skid protection. In this occurrence, the BOV operating levers of tank cars TILX 192186 and PROX 76346 met AAR design requirements yet failed to prevent product loss as both levers were bent and both BOVs opened and released substantial amounts of product.

Following the 2009 investigation into the Canadian National Railway (CN) freight train derailment in Cherry Valley, Illinois, the National Transportation Safety Board (NTSB) of the United States (US) determined that “existing standards and regulations for the protection of bottom outlet valves on tank cars do not address the valves' operating mechanisms and therefore are insufficient to ensure that the valve remained closed during accidents.” The NTSB subsequently recommended to the US Pipeline and Hazardous Materials Safety Administration (PHMSA) that it:

“Require all bottom outlet valves used on newly manufactured and existing non-pressure tank cars are designed to remain closed during accidents in which the valve and operating handle are subject to impact forces. (R12-6). “

To date, the recommended changes have not been made and, as demonstrated in this accident, these types of releases continue to occur during derailments. With over 220,000 Class 111 tank cars currently in service in North America, many of which transport DGs, and their propensity for BOV operating lever failure resulting in product loss during accidents, Transport Canada may wish to review the BOV operating lever design requirements for Class 111 tank cars.

Yours sincerely,

Original signed by Kirby Jang

Kirby Jang
Investigation Operations Rail/Pipeline

Luc Bourdon, Director General, Rail Safety – TC
Karl Alexy, Staff Director, Hazardous Materials Division - FRA
Magdy El-Sibaie, Associate Administrator for Hazardous Materials Safety- PHMSA
Robert Hall, Director - NTSB
Glen Wilson, Vice President Safety Environment and Regulatory Affairs - CP
Michael Bourque, President and Chief Executive Officer - RAC
Ken Dorsey, Executive Director, Tank Car Safety - AAR


TSB Occurrence::
R13T0060 (Class 3)
Rob Johnston
Manager, Head Office & Central Regions
TSB Ottawa, ON
(819) 956-8736