Improving the Safety of Railroad Tank Car – Final Rule
2:16 AM MDT | April 20, 2009 | By STEVE ROBERTS
On Tuesday, January 13, 2009, the Department of Transportation’s Pipeline and Hazardous Materials Safety Administration (PHMSA) published their Final Rule on PIH Tank Car Safety, to be effective on March 16, 2009. This Final Rule is based on both the Notice of Proposed Rulemaking (NPRM), published on April 1, 2008, and the petitions for interim standards for PIH rail car construction, published on July 23, 2008. The Final Rule implements operational controls to reduce the severity of crashes of rail cars transporting materials that are poisonous by inhalation (PIH), and also addresses the issue of PIH rail car construction standards by implementing interim design standards for PIH rail cars that will increase rail car survivability in the event of a crash.
PHMSA opted for an incremental increase in the crashworthiness of PIH rail cars instead of the wholesale redesign proposed in the April NPRM. As a result of industry comments and the petitions for interim standards, PHMSA decided to issue an interim construction standard with increased shell and/or jacket thickness and a requirement for full head shields. Additionally, the Final Rule implements new requirements for enhanced protection of top fittings protection systems and nozzle arrangements.
PHMSA does not intend that the entire fleet of PIH railcars be replaced with cars meeting the interim standard; rather, PHMSA wants fleet owners to use rail cars manufactured to these interim standards to replace cars that have reached the end of their service life or those that have been damaged and must be removed from service.
The final rule also addresses train operations in order to reduce the severity of accidents that do happen. The main issue addressed by the interim rule is speed limits for hazmat trains, with implementation of “a proposed 50 mph speed limit for all loaded, placarded rail tank cars used to transport PIH materials.” 74 F.R. 1785. PHMSA did not include the proposed interim 30 mph speed limit in dark territory for PIH cars not meeting the proposed enhanced design requirements because those requirements do not yet exist. PHMSA has identified other measures that allow “DOT and the railroads to develop ways to target and address excess risk in dark territory.” 74 F.R. 1781.
Rail cars containing PIH material residue will not invoke the 50 mph speed limit for trains. While there is a risk associated with even a small leak of PIH material, PHMSA believes that the reduced weight of a PIH residue-containing rail car will decrease the likelihood of a leak. Also, the potential extent of a PIH cloud is much less severe for a car containing only material residue. The combined risk reduction caused by these two factors means that the reduced speed limit is not needed, although PHMSA encourages railroads to apply the 50 mph restriction to residue shipments when possible.
Operational Life of Interim Standard Rail Cars
One of the more contentious issues raised in the comments to the NPRM was the lifetime of new cars introduced into the PIH fleet between the effective date of the rule and the introduction of the enhanced design described in the NPRM. The NPRM would have required the complete replacement of the PIH fleet within eight years after promulgation of the Final Rule. PHMSA does not address that issue in this Final Rule. They do note, however, that the interim standard railcars will be expected to “have a useful life of at least two decades.” 74 F.R. 1781.
This rule will allow PIH rail car fleet owners and rail car manufacturers to resume upgrading their PIH rail car fleet with assurance that the replacements will have a reasonable economic life. The uncertainty caused by the NPRM has now been greatly reduced. Older, less safe rail cars can now be replaced with rail cars that are incrementally safer than the newer cars in the existing fleet, and rail car fleet owners will continue to ensure compliance with DOT rules.
You can reach Steve Roberst direct at www.chemicalsecurity.com