Deaths of oilfield workers over the years indicate there may be a safety gap when it comes to exposure to vapors in above ground storage tanks. Most recently, a 21 year-old worker was found dead on top of a steel storage tank. His job was to measure the oil level by dropping a rope down into the tank from an access hatch on top. Based on hydrocarbons found in his blood during the autopsy, it is believed he was overcome with petroleum vapors, passed out, and then died from continued exposure.
While API-650 addresses construction an above ground storage tank for safety in durability, there is not a separate specification that addresses hazards related to vapor exposure of a tank in operation. There are no laws prohibiting measuring oil level with the rope method, but some people think there should be. They believe installing automated measuring equipment would save lives. One problem is that two agencies with jurisdiction over the oil industry have somewhat conflicting concerns.
The National Institute for Occupational Safety and Health (NIOSH) has warned the oil industry about the hazards of the rope measurement technique, but the Bureau of Land Management (BLM) requires accurate accounting of oil levels to properly represent taxpayers, because royalties are paid on the amount of oil removed from the ground. Most API-650 tanks storing oil do not have automated measuring devices, so most companies resort to the rope method. Furthermore, the BLM is not confident that current automated measurement technology is as accurate as the rope method. Furthermore, adding an automated measuring system costs approximately $2,000. If BLM regulations were updated to require such systems on every API-650 oil tank, some above ground storage tank owners would go out of business.
Interestingly, offshore oil storage containers and steel storage tanks tend to use automated oil level measuring. They are not governed by the BLM however. But many in the industry think the move to automated measuring techniques for onshore storage tanks would help save lives.
Food Service Industry
And lest one think that petroleum vapor is the only hazard when it comes to steel storage tanks, look what happened in Johnson City, New York at a sauce making facility. While cleaning a steel storage tank, a worker was overcome by vinegar fumes from the vinegar that had been stored in the tank. He was seriously injured, had to be taken to the hospital, and was held there for five days. OSHA fined the company $80,000 for safety violations.
“This incident, and the resulting severe injuries to this worker, should never have happened,” Christopher Adams, OSHA’s Syracuse area director, said in a statement announcing the fines. “Workers who enter confined spaces risk being overcome, sometimes fatally, by toxic and oxygen-deficient atmospheres.”
Use Caution Around All API 650 Tanks
While the incidents of the deaths in the oil field are unrelated to the injury of the food service worker, it still highlights the dangers that toxic fumes pose to workers in the confined spaces of an API 650 tank. Time will tell if there will be new legislation to address these hazards, but as an industry there are preventive measures that can be put in place now to address these dangers. Whether working with oil storage tanks, food processing storage tanks, or fertilizer storage tanks, always tank precautions for ventilation when working around or entering such a confined space.