December 12, 2018

JR gestures | The Japan Times

JR gestures | The Japan Times: Dear Alice, Until recently I lived in Tokyo and commuted on the JR Chuo Sobu Line from Kameido Station. I made it a practice to ride in the last compartmen

December 8, 2018

Safety And Reliability: Two Sides Of The Same Coin

Safety And Reliability: Two Sides Of The Same Coin: Maintenance and reliability efforts are critically important in today’s industrial environment where increasingly complex and interdependent equipment are utilized.

December 3, 2018

Another Bhopal Anniversary.....

Time flies, but for the people who died a gruesome death on 2nd/3rd night, 1984, time was irrelevant. Today, we are in the cusp of technological innovations in process safety management, but the moot point is....can technology alone prevent disasters? Its people who make decisions, decisions that may compromise process safety and that could lead to a loss of containment incident. I am always of the view that technology can only be an enabler, if properly used.
There is a welcome change in India. Increasingly, boards of directors of chemical companies are focusing not only on occupational health and safety, but also on process safety. This is a welcome change. Lets pledge not to have another Bhopal again.

November 30, 2018

Choke clearing incident

A senior maintenance member of a two-man crew, and another employee were working from an elevated work platform. The platform was mounted on the back of a trailer, which was mounted to an asphalt tank. The employees had begun bypassing the normal asphalt storage tank to prepare for its five-year to seven-year cleaning. They placed a bypass valve in position to route the asphalt from the permanent tank to the temporary, trailer-mounted tank. Most of the asphalt piping was heated with a steam jacket encircling the pipes. However, the piping that ran from the bypass valve to the temporary tank was encircled with tubing that was heated by steam. The employees complained that the steam tubing, also referred to as steam tracing, was not wrapped tight enough, thereby preventing the pipe from getting hot enough to turn the hardened asphalt back to its liquid (melted) state. The employees then attempted to repair the clogged pipe. As was reported to be the normal practice, they went to the end of the asphalt piping outlet and began heating the last bend of the piping with a propane torch. The piping outlet was located directly over the top of the manhole opening of the heated asphalt tank. The tank was reported to be 300 degrees to 400 degrees Fahrenheit, at that time. During the site visit, approximately five hours later, the tank temperature gauge read approximately 260 degrees Fahrenheit. After an undetermined amount of time that the employees were using the propane torch to heat the piping, an explosion occurred in the asphalt tank. A witness described the explosion as a flame which shot 30 feet above the manhole cover and quickly descended back into the tank. This witness also stated that he could no longer observe the employees standing on the platform. Employee #1 remained on the platform and suffered asphalt burns and fractures to his face, where an item impacted it during the explosion. Employee #2 fell from the work platform, approximately 9 feet 5 inches to the concrete surface. Employee #2 suffered asphalt burns to his body and face, in addition to a hip fracture. A radio call for emergency response was broadcast throughout the company. The company Emergency Response Team doused the flames and provided initial first aid to Employees #1 and Employee #2. Both employees were transported to the hospital.

November 10, 2018

Minimizing Fire and Explosion Hazards in dusty systems

Minimizing Fire and Explosion Hazards in Dusty Systems: Having honest conversations about material handling hazards allow risks to be properly addressed, thereby reducing fire and explosion threats.

November 2, 2018

12 Tips for Centrifugal Pump Safety

12 Tips for Centrifugal Pump Safety: Centrifugal pumps are used in industrial settings, and there are several steps that should be followed to ensure safe and efficient pump operation.

October 29, 2018

On April 6, 1994, a unit operator was conducting rounds of the coker unit when he observed a leak coming from the mechanical seal of the heavy gas oil pump of coker unit #1. The operator decided to seek assistance; the head unit operator and six or seven unit operators responded. The operators placed water and steam on the leak to suppress the vapor from the seal. The head unit operator decided to shut down the pump and transfer the product to the secondary pump. As the operator shut down the primary pump, the mechanical seal blew, causing a vapor cloud to generate from the seal. The operators continued to put steam and water on the seal and isolated the pump from the pipe line. The remaining product in the pipe line leading to the primary heavy gas oil pump vaporized, leading to the dispersion of the vapor cloud. The operators who responded were wearing bunker gear and several wore emergency respirators. Those with respirators isolated the pump from the pipe line by closing the suction and discharge valves. The operators who were not wearing emergency respirators stationed themselves upwind of the vapor cloud and put water on the cloud; however, the wind changed direction several times, exposing unprotected operators to vapors. Employees #1 and #2, two unprotected operators who responded to incident, were brought to Hospital to be treated for inhalation of hydrocarbons. Employee #1 was hospitalized.
Source: OSHA

October 24, 2018

Hexane Vapors Ignited By Static Electricity; Worker Burned

Employee #1 was standing at the exit end of a conveyor, peeling off a build up of hexane adhesive from the inside of a stainless steel dip tank. A static discharge of electricity, apparently generated by the peeling action, caused a flash fire. Employee #1 suffered second degree burns on the back of his hands and his upper chest and neck. The tank is 12 inches by 15 inches by 22 inches in size. The employee was pulling adhesive from the back side of the tank when the fire started. All the equipment in the area is grounded and bonded and approved for the location. The flash point for hexane is -23 degrees.

September 18, 2018

Leak due to vibration

A specialized rubber manufacturing plant experienced leakage of a hexane solution from a pump discharge flange during use. The hexane vapor was ignited by a st atic electricity spark and a fire occurred. Apparently, the flange was loosened by vibrations from the pump.Routine operations were being carried out on site at the time of the accident.
The operation involved the transfer of a hexane solution from an un-reacted raw material recovery tank to the washing process through the outlet of the first flange of the pump. The hexane solution
leaked, ignited, and burned. The financial costs of recovery and lost production were significant.
The cause of the accident was a loose flange that resulted in leakage of a flammable substance. During the operation, a previously undetected cavitation in the pump produced significant vibration
which loosened the flange. As a cause of the ignition it was considered that the hexane was charged when it spouted from the flange, and static electricity was discharged; then hexane vapor ignited
and a fire occurred.
It was considered that the vibration might have been intensified by the passage of an insoluble polymer lump through the pump, a malformation in the substance generated on the piping wall. In addition, a reducer connected a 3-inch (~75mm) flange of the discharge pump to 6-inch (~150mm) piping. The looseness of this flange might have been accelerated when the force
of vibration was added on the piping.
Lessons learned
Vibrating equipment can increase potential for stress fractures and gaps from loosely fitting interfaces, all of which can be sources of leaks that, if undetected, may result in an accident. It is necessary to pay sufficient attention to vibrating equipment, especially pumps that may be found in many processes throughout the site. Control measures to mitigate potential risks could include regularly scheduled inspections in line with existing technical standards or in-house experience, particular attention to small-bore piping (vulnerable to fatigue), installation of a  vibration monitor to detect and locate abnormal vibration patterns, as well as other measures available in guidance
on vibrations from numerous sources.
Source: European Commission

September 14, 2018

Common Causes of Gasket Failure

Common Causes of Gasket Failure: During the course of our 50 years in business, Associated Gaskets has seen many different types of gasket failures. Sometimes these were seen late at night when we were called out to help with an emergency, other times it was when one of our own gaskets was returned after failing …

September 6, 2018

Global warming and its effect on process incidents

As the effects of global warming are being felt, chemical industries must acknowledge the fact for planning for natural disasters. The "Fire from ice" video about the Valero refinery incident and The Arkema incident due to Hurricane Harvey are two examples related to climate. Cyclone maximum wind speeds are increasing and past weather data may not be a reliable predictor about the future. What are you doing about it?

September 3, 2018

Gasket failure incident

On 5th January 2008 a production operator discovered a fair sized phenol leak in the phenol pump house next to the phenol storage tank. One of the gaskets on the flange connection on the outlet pipe of the tank had failed. The head of the operations department tried to stop the leak by tying a rubber belt around the flange. In the meantime, an operator sprayed water on the flange to avoid contact with phenol as much as possible. The phenol that had leaked was collected in a catchment pit of 20 m3 underneath the pump house. This catchment pit had a high level alarm, but it was not functioning at the time of the leak. The company was not aware of the malfunction because the alarm was not subject to periodic inspection.
An attempt was made to close the only manual valve on the pipe,located between the inner and the outer tank shells, but the valve spindle broke off during this manipulation, so the line could not be
shut off. After the temporary repair of the flange connection, three leaks continued to release phenol, which were also collected in the catchment tank. It was not allowed for the employees to enter the
pump house while the phenol was leaking. To clean up the catchment pit, the company provided a waste tank big enough to contain all the leaked phenol. When starting to pump the phenol from the catchment tank to the waste tank, it was discovered that the catchment pit had overflowed. Part of the
phenol/water mixture had passed over the rim of the open pit into the municipal sewer system. At the time, it was not yet known how much phenol had leaked to the sewer system.
On 7th January 2008 it was decided to start up the phenol-based batch production to consume all phenol in the storage tank since the phenol tank had to be taken out of service in order to replace
the gasket on the flange. On January 8th, after a few batch productions, it was found out that the level indicator in the phenol storage tank had become stuck since the last control of the level on 4th January (comparison of manual level measurement with level indicator). Only at that moment did the company realize that 25t of phenol had leaked out of the tank. The catchment pit probably
collected most of the release, but more than 5t of the phenol spilled into the municipal sewer. No consequences were reported as a result of the release into the municipal sewer. A specialized
company was hired to repair the remaining phenol leak.
In this case, a variety of causes contributed to the accident. The direct cause was the degradation of gasket that caused the leak. After the flanges and valves were replaced following the accident, it
was discovered that the valve broke down because the gasket next to it had been reacting with phenol over the course of many years, leading to a solid deformation that prevented the valve from moving,
hence, the valve could not be closed. The spindle of the manual valve at the tank broke off as a result of the deformation of the adjacent gaskets.
Source: European commission

August 27, 2018

Rupture of sulphuric acid tank

On 4th February 2005 a storage tank containing 16,300 t of 96 % sulphuric acid ruptured. The entire contents of the tank were spilled out into the bund and then overflowed out into the nearby dock. The environmental consequences of the accident were quite significant,the sulphuric acid emission had a serious effect on local flora in the inner and deepest parts of the harbor and harbor entrance area. When the sulphuric acid came into contact with the salt water an exothermic reaction occurred, producing a vapour cloud consisting of hydrogen chloride that drifted northwards along the coastline in the direction of the wind. Fortunately, the wind was blowing towards the sea and away from populated land areas and the cloud diluted very quickly. After the spill approximately 2,000 t of contaminated sulphuric acid remained in the bund. The acid also soaked into about 100,000 square metres of the ground surrounding the spill.
The cause of this incident was a leak in an underground coolant supply pipe of reinforced concrete installed over forty years before that resulted in a weakening of the ground under the tank farm. Apparently, water forced its way out of the pipe, eroding the ground near and around the sulphuric acid tank. This erosion damaged the ground under the tank which ultimately failed due to the lack of support of the tank floor. A study of the appearance of the involved part of the coolant supply pipe suggests that the corrosion was a result of an acidic attack on the concrete.
Important findings
• The damage indicates that the acid exposure occurred over a long period of time. However, it was not possible to determine the exact duration of the exposure.
• The pipe had been in use over many years and the operator had mno suspicion that the pipe was suffering severe degradation. The inspection of the failed pipe after the incident detected little or no internal corrosion, but heavy external corrosion to the concrete. In certain places the concrete had corroded so severely that the reinforcing steel was exposed.
• According to the German standard, DIN 4030 (equivalent to the European standard, EN 260) a strong attack on concrete occurs if the pH level in surrounding water is < 5.5 and a very strong attack can occur if the pH level is < 4.5. Fifteen years before the accident a ground pollution study was carried out in the area, during which one of the sample taking points was close to the failed coolant supply pipe. At this point the pH level was measured at 4 in the shallow groundwater. With this knowledge the company drew the conclusion that this pH level entailed risks for strong acidic attackson the concrete.
Lessons learned
• The uneven corrosion on the outside of the pipe can possibly be explained by the fact that it lay partly in groundwater flow. In this environment, the acid can pass through the barrier more easily, and the reaction products (gypsum) formed can be more easily dissolved. As such, the concrete barrier was not as effective as on the part of the pipe that remained in drier surroundings. Therefore, concrete piping exposed to ground water should be should be subject to protective measures, monitoring and inspection to take into consideration the increased risk from groundwater exposure.
• Similarly, underground piping that entail risks to foundations should be inspected and measured..
• There are a number of strategies that can be applied to piping where there is accelerated potential for degradation or where there are high consequences should significant degradation occur.
Pipes may, for example, be tested for stability (remains in place) and hydraulically checked on a regular basis. Alternatively, consideration should be given to positioning the pipe above ground. The pipe could also be placed in casings, especially where a leak may cause damage to the surroundings or where pressure and ground deformation may cause damage to the pipe.
Source: European commission