Those of you that have followed me and my ramblings for years know that I am a stickler for unloading/loading operations involving HAZMAT(s). Some of the worst accidents in my career in the chemical industry involved the unloading/loading of HAZMATs. I have written many times about the hazards of unloading even mildly hazardous materials into the wrong tank resulting in serious consequences or about hose failures and even drive-off incidents, all resulting in serious consequences. I am often told that “truck unloading/loading” is “outside the scope of your audit” but I forge ahead knowing the potential outcomes if the issues we identified go unchecked! Now the Pipeline and Hazardous Materials Safety Administration (PHMSA), a part of DOT, has published a “Best Practice” manual for Cargo Tank Motor Vehicle (CTMV) Loading/Unloading operations. This document is intended to aid hazmat employers and others responsible for cargo tank motor vehicle (CTMV) loading/unloading by offering recommended best practices to further enhance the safety of these operations.
Human error continues to be a major contributing factor for incidents occurring during loading/unloading operations including but not limited to:
Failing to attend/monitor loading/unloading operations;
- Leaving a valve in the wrong position either prior to, during, or after loading/unloading operations;
- Improperly connecting transfer equipment;
- Overfilling cargo tanks or receiving tanks; and
- Using defective/deteriorated devices and equipment.
The following incidents illustrate the need for loading/unloading guidance:
- In June 2013, a driver miscommunicated critical information to facility personnel during delivery of corrosive material that was then unloaded into the wrong storage tank containing incompatible materials. Adding to the confusion, this was the driver’s first delivery to this location. The co-mingling of incompatible materials emitted a vapor affecting the breathing of the driver and facility employee resulting in both being transported to a hospital for treatment. Also, approximately 100 gallons of the mixture was released at the time of unloading.
- In November 2011, a carrier loading heating oil into a cargo tank overfilled one of the compartments resulting in the release of approximately 30 gallons of material. The cause was determined to be faulty operation of the high-level sensor.
- In July 2009, the transfer hose on a CTMV ruptured following the transfer of anhydrous ammonia from a cargo tank to a storage tank. The resulting release of anhydrous ammonia caused one fatality, minor respiratory problems for several individuals, and the sheltering in place of nearby residents. An investigation determined the probable cause of the accident was the use of a transfer hose assembly not chemically compatible with anhydrous ammonia.
- In October 2007, a delivery driver used an improperly repaired transfer hose to unload LP gas from his 8,000-gallon cargo tank. The hose detached from its connection to the vehicle’s cargo tank allowing gas to escape, resulting in an explosion that fatally injured the driver. The accident investigation revealed workers improperly repaired a damaged LP-gas transfer hose by attaching a nozzle using fasteners not designed to withstand pressurized gas. The Federal Motor Carrier Safety Administration has issued guidance regarding this incident, and cargo hose safety at: https://cms.fmcsa.dot.gov/safety/carrier-safety/important-notice-regarding-anhydrous-ammonia-and-liquefied-petroleum-gas-hoses
PHMSA believes focused training and recommended operating procedures can help decrease these types of incidents. Even when human error was not the main reason for an incident or accident occurring, focused training and recommended operating procedures could help avoid them in the future.
This Best Practices Manual ALSO gives us DOT’s position on how Unloading/Loading PSM/RMP covered chemicals associated with a “covered process” are covered by OSHA/EPA/DOT (see appendix B).
CLICK HERE to download this EXCELLENT resource