If you were in Houston in the Summer of 1976, you remember the deadly tanker truck crash of May 11 that year. Just after 11 a.m. on that fateful morning, a half-loaded tanker truck hauling anhydrous ammonia failed to make the curve from the West Loop 610 northbound to the Southwest Freeway (59) southbound, and plunged over the side. Excessive speed was blamed for the accident, which killed the 28-year old driver, William Gregory Schmidt, and 6 others, hospitalized 78, and injured more than 100.
Investigators would later determine the truck was traveling onto the ramp at over 53-mph. The liquid gas in the half-filled tank shifted, forcing the rig out of control, through the guardrail, and over the side. When the tank ruptured, a white fog of ammonia gas enveloped the freeway exchange, suffocating, burning or scarring for life those caught in the fog. (Source.)
In response to this and other tanker accidents, the Federal Motor Carrier Safety Administration has developed new guidelines for tanker trucks.
The FMCSA’s “Cargo Tank Roll Stability Study” cites rollovers as being among the most serious crashes of cargo tank motor vehicles carrying hazardous materials.
“They are more likely to be fatal to the driver of the vehicle than other crashes, and they can cause spills and necessitate highway closures.” This study reviewed cargo tanks, “from design through operation, to improve their roll stability.”
You can review the entire study, which was born out of accidents like the 1976 tragedy, HERE.