Process Safety - Old is Gold If.....

A news report about an accident at a refinery in USA mentions that the cause of the incident was lack of inspection and maintenance of decaying 40 year old equipment. How are your maintaining your "old" equipment? Are your inspection philosophies revisited based on operating and maintenance experience? Personally, I have seen huge water pumps that are over 40 years old and are still supplying water to a large chemical manufacturing unit in India. The pumps are well maintained and look good enough to run for another 10 years!
The article mentions the following:
"On Monday, Silverstein said his inspectors determined the Anacortes accident was caused when a 40-year-old steel heat exchanger ruptured and spewed vapor and liquid that immediately exploded. Tests showed welds in the exchanger had developed cracks over the years. The rupture occurred along those weak points as the equipment was coming back online after maintenance.
Tesoro hadn't properly inspected the exchangers since 1998, and even then didn't test the most vulnerable areas, Silverstein said. Tesoro had planned to test them in 2008, but never did.
"If they had, we believe, they would have found the cracks that caused this explosion," Silverstein said. "They would have prevented this horrible incident from ever happening."
All seven workers who died had been standing near the exchangers. They were there in part, Silverstein said, because Tesoro had been unable in recent years to stop the equipment from leaking volatile, flammable gases.
So employees were positioned around the machinery in hard hats, gloves and goggles with "steam lances" — long tubes — they used to disperse the vapors. They also had to manually adjust valves during startup to make sure leaks didn't get out of control.
Read the full article in this link

The Human and Process Safety

Why is that we do not seem to learn lessons from incidents? One of the root causes of the 2005 BP Texas refinery incident was attributed to operator fatigue and overload. In many cases lack of training and troubleshooting skills are also mentioned. Do not neglect such warnings. An article mentions the following about the San Bruno gas pipeline accident:
"The San Bruno natural gas explosion has underscored a growing concern about the capabilities of utility employees who watch over the nation's pipelines and whose errors have been linked to a number of mishaps, some of them catastrophic.
The National Transportation and Safety Board has said among the questions it is investigating is whether workers at a PG&E pipeline-monitoring terminal in Milpitas were fatigued or poorly trained. And just eight days after the Sept. 9 blast, the federal Pipeline and Hazardous Materials Safety Administration moved to speed up adoption of a rule to insure that workers doing similar jobs at companies across the country are well-trained and rested -- especially since many of those workers put in 12-hour shifts".
"A 2005 NTSB study that scrutinized 13 pipeline mishaps involving various liquids from 1992 to 2004 found that "in ten of these accidents, some aspect of the SCADA system contributed to the severity of the accident." In many cases, the problems were aggravated when workers monitoring the systems failed to quickly recognize and respond to leaks. Among the accidents cited:
# An April 7, 1992, fire in Brenham, Texas, that caused three deaths and 21 injuries after a poorly trained worker failed to notice the changing pressure in a pipe, in part because the system didn't display data in a way the worker could easily interpret.
# On June 10, 1999, a worker failed to realize that a gasoline pipeline had ruptured and burst into flames in Bellingham, Wash., because the malfunctioning control system was providing erroneous data. As a result, it took more than an hour to shut the pipe's valves. Three people died and eight were injured.
# On Oct. 27, 2004, after a pipeline containing the caustic and potentially deadly chemical anhydrous ammonia ruptured in Kingman, Kansas, a worker misinterpreted alarms generated by a control system and mistakenly increased the flow of ammonia into the line. No one was killed or injured, but 204,000 gallons of the liquid flowed into a creek, killing more than 25,000 fish, including some threatened species.
"From 1990 to 2009, gas-line operator errors caused a little more than 5 percent of all the significant accidents nationwide, resulting in 8 fatalities, 150 injuries and $16.2 million in property damage, according to data kept by the Pipeline and Hazardous Materials Safety Administration. During the same period, operator error caused 11.5 percent of "serious incidents," which involve a fatality or an injury requiring hospitalization".
Read more of the article in this link.

Flammable gas detectors - use them properly

Flammable gas detectors which are widely used in the chemical industry are often not properly maintained. The use of improperly or wrongly calibrated detectors will lead to a false sense of security and may cause an accident. Read the guidelines given by International safety equipment association in this link

Explosion in Fertiliser plant in USA

A news article has reported an explosion in a fertilizer plant in USA. It is reported to have occurred due to a rupture of a high pressure Urea Ammonium Nitrate vessel.The noise from the explosion was reported to be louder than a sonic boom. Read more of the article in this link.

Don't underestimate the power of water!

In 2009, a massive failure of the power generation turbine at a hydroelectric plant in Russia killed about 74 people. According to Wikepedia, the root cause was attributed to lack of complete bolting of the turbine casing cover. The consequences were horrendous.Do not underestimate the power of water in a process plant. Water hammer, flashing of water into steam are hazards that can cause severe damage to plant equipment. Train your operators on these hazards.
Read about the failure in this Wikepedia link.
See amazing photos of the disaster in this link.