Source: The Agricultural Retailers Association

The Agricultural Retailers Association said the 2003 nurse tank failure in Calamus, Iowa, led to an investigation by the National Transportation Safety Board. As a result, NTSB recommended to the U.S. Department of Transportation (DOT) that periodic testing be required on nurse tanks.

In 2004, DOT granted The Fertilizer Institute's request for a special permit for nurse tanks without the required ASME identification plate. The special permit program allows these nurse tanks to remain in transportation so long as certain tests are performed and passed. Those tests are an external visual test, pressure test and thickness test- all to be conducted every five years.

During November 2008, DOT performed nurse tank inspections in several states and found substantial non-compliance with the current nurse tank testing laws. Therefore, the DOT has issued a safety advisory to anhydrous ammonia nurse tank owners and handlers. The advisory describes how to comply with current nurse tank maintenance and testing regulations.

Furthermore, the outstanding NTSB calls for testing of all anhydrous ammonia nurse tanks, and the DOT is asking industry to guide it in formulating the regulation. Thus, ARA is supporting TFI's petition for rulemaking to the DOT. The petition asks that the DOT require testing of all anhydrous ammonia nurse tanks. The petition requests that the DOT write a rule that is much like the Special Permit Program, with the additional provisions of a 5-year phase-in period for compliance and thickness testing on non-plated tanks only. Additionally, ARA pushed for "self-certification" language to also be included in the petition so that facilities may continue to train staff to perform the inspections.