The National Propane Gas Association (NPGA) is reminding its members that another deadline for retrofitting bulk plants is coming July 1. While most attention over the last several years has been paid to the deadline for the internal valve retrofit for bulk plants and industrial installations, NPGA notes that date also requires that piping be designed to prevent debris from impeding the action of valves and other components.
The provision, found in 22.214.171.124 of the 2011 edition of NFPA 58, requires a strainer or other device to be installed at the loading riser to capture stones and other foreign material that may find its way into truck and plant hoses. The provision first appeared in the 2008 edition of NFPA 58. The requirement was introduced into the code in the 2001 edition when the internal valve retrofits were being implemented.
Both requirements were introduced as a result of the 1996 incident in Sanford, N.C., where about 45,000 gallons of propane were released when a transfer hose separated and the back-flow check valve failed to operate. It was determined that debris had impacted the flapper on the valve and broke it. Subsequently, North Carolina officials began testing all back-flow check valves in the state and found that about 8% were not operating properly, mostly due to debris in the system that was stuck in the valve, preventing it from closing.
NPGA comments it wasn’t until the 2008 edition of NFPA 58 that the retrofit requirement came into the code. Between 2001 and 2008, the requirement for installing a strainer or other protective device only applied to new installations. However, the NFPA Technical Committee on Liquefied Petroleum Gases decided that since the fix was relatively simple, it made sense to require existing plants to comply, and the
July 1, 2011 deadline was chosen to coincide with the internal valve retrofit requirement.
TransTech Energy is a leading NFPA retrofit contractor, serving a broad list of industrial and propane retailer clients nationwide. For a consultation and free plant review to ensure your bulk plant is in compliance with the most current NFPA guidelines, contact us today.