During my PHAs and Audits, I typically find businesses that are not focused on the UNLOADING risks associated with their hazardous materials. I tend to get a lot of pushback about how Unloading is a DOT function and somehow not related to process safety. The risks associated with unloading 7,000 gallons of an HHC/EHS through “temporary connections” and a “hose(s)” may be the highest risk for many businesses. And therefore, I tend to spend time discussing the controls/barriers/safeguards the business has in place for this risk/operation. As we have discussed many times, the IFC and several chemical-specific RAGAGEPs (e.g., CGA 2.1, NFPA 58) have great designs for this operation. And just recently, the CSB issued a report on the value of “remote isolation devices” in these operations. But there tends to be an overlooked need when it comes to pre-use, monthly, and annual inspections/testing of unloading hoses (liquids/gases and vents).
PHMSA wrote a “2012 letter” after the SC NH3 fatal release related to the catastrophic failure of a transfer hose. This letter explains the inspection needs well…
As part of an investigation of an accident involving the rupture of a hose used to transfer anhydrous ammonia, the National Transportation Safety Board (NTSB) included among its findings the belief that lack of clarity of § 180.416(d)(1) regarding monthly inspections of each “in service” hose assembly can lead a cargo tank motor vehicle operator to defer monthly inspections mistakenly. The NTSB concluded that “if a motor carrier does not believe that [a hose assembly] will be used, it will not necessarily consider it to be “in service” and as a result, the hose assembly may not be inspected, as was the case in this accident.” It is the understanding of NTSB that a hose assembly carried on a cargo tank motor vehicle has the potential to be used on any given day and, consequently, is “in service.” Therefore, in order to provide greater clarity of the monthly inspection requirement of a hose assembly installed or carried on a cargo tank, in its Safety Recommendation H-12-5, the NTSB requests that PHMSA provide an interpretation of when a hose assembly is “in service.”
A hose assembly installed or (to be) carried on a cargo tank motor vehicle (CTMV) in a liquefied compressed gas service MUST be inspected monthly regardless of whether it is used in any given month. Although a hose assembly must be checked before each unloading operation, this check involves only readily visible components (see § 177.840(m)). The requirement of § 180.416(d)(1) ensures that AT LEAST ONCE A MONTH each hose assembly assigned to a cargo tank motor vehicle in liquefied compressed gas service will undergo a thorough visual inspection whether or not it has been used.
“In service,” as used in § 180.416, is associated with qualification and maintenance for purposes of hazardous materials transportation and should NOT be misconstrued as “in use.” Just as a cargo tank in liquefied compressed gas service is subject to inspection and testing requirements and must be removed from hazardous materials service (i.e., placed out of service) if it fails a test or inspection, a hose assembly must be inspected and tested, and removed from service according to rejection criteria found in § 180.416. A repaired hose assembly successfully retested in accordance with § 180.416(f) may be placed back in service and then must again be inspected monthly regardless of whether it is used in any given month.
Source: https://www.phmsa.dot.gov/regulations/title49/interp/12-0121