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February 27, 2012

Plane accidents and process safety


"06/23/1967 Mohawk Airlines
BAC-111-204AF Blossburg, Pennsylvania The airplane crashed after an in-flight fire destroyed the pitch control systems. All 34 people aboard were killed. A malfunctioning nonreturn valve allowed hot engine bleed air to flow back through an open air delivery valve, through the APU and into an acoustic blanket lined section of the fuselage. This caused flexible hoses with hydraulic fluid to ignite and lead to an uncontrollable fire".
Beware of check valves!!

"09/06/1971 Pan International
BAC-111 Hasloh, Germany The aircraft collided with a bridge, shearing off both wings, after a double engine failure occurred during takeoff. The water-injection system to cool the engines during takeoff was inadvertently filled with kerosene instead of water".


30 years ago, an operator in the plant I worked filled up antifoam liquid from a drum similar to an oil drum into the hydraulic governor of a large steam turbine. We found out when the governor started misbehaving!!

Source of plane accidents : http://planecrashinfo.com/unusual.htm

February 25, 2012

Fire in Pharma factory

Reports of a fire incident in a Pharma factory mention that hazardous waste stored for incineration caught fire. Are you safely storing hazardous waste as per the norms? Generally, what I have observed in other factories is that the incinerator area, being far away from the plant, sometimes gets a little less attention than it should be getting. Most of the work is also contracted out.Ensure that the contractor employees are trained in the norms of handling, storing and processing hazardous waste.
Read the article about the fire in these links:
Link 1
Link2

February 24, 2012

The importance of emergency stopping

How do you ensure that your emergency stop buttons will work when needed? The emergency stop is the last line of defense and a good article by Robin J Craver mentions the following:
"The nature and operation of the machine must be considered.
· Is it safe to have the emergency stop system cut the power to the machine drives and actuators? This may result in the hazard “free falling” leading to a more dangerous situation.
· Should the system actuate a brake or clamp?
· Would stopping the machine in position result in a worsening of an injury?
· Should the system allow the machine to continue on or reverse to a safe position?"

 Read the article in this link.

February 22, 2012

Process safety and nanotechnology

With nanotechnology, the process safety hazards will change. A whole new nano process safety approach may need to be taken to identify nano hazards. An article mentions the hazards of nano dust. It mentions that "nanomaterial dust could explode due to a spark with only 1/30th the energy needed to ignite sugar dust — the cause of the 2008 Portwentworth, Georgia, explosion that killed 13 people, injured 42 people and destroyed a factory".
Read the article in this link.

February 19, 2012

Fire in refinery

A fire in a major refinery in the US has been reported. Apparently, the fire was due to a flange leak.See the video of the fire in this link.

Pressure vessels and labs / R & D's

I have often seen that personnel in labs and R & D setups do not understand the hazards of a pressure vessel. Many times, pilot plants are built by buying equipment from the second hand market. Not having the specifications / data sheet for the vessel is dangerous. One such fatal incident in a NASA lab highlights the following:
"Vessel at least 33 years old
• Unknown prior service, no nameplate, no drawings
• No pressure or temperature rating information
• Most welds on hold down bolts were cracked before being put into this service

.Vessel design inappropriate for intended service
– Vacuum vessel put into service as a pressure vessel
• Vessel not pressure checked prior to full use
– And no restricted access during initial pressurization
• Critical welds on hold down bolts not inspected after 33+ years of existence
– Were not considered critical for a negative pressure (vacuum) application
• Bolt welds were cracked and cracks exhibited corrosion prior to this use
• Vessel failed (chamber lid separated from chamber body) when all hold down bolt welds broke simultaneously".


Read about the incident in this link.

February 17, 2012

Industrial accidents in India

As interesting article in Livemint.com highlights that statistics of industrial accidents in India are not accurate. It mentions that "Data supplied by two labour ministry agencies show that accident insurance benefits claimed by companies indicate a rate of accidents that far outweigh those that are reported".
Read the article in this link.

February 15, 2012

Ammonia gas leak incident

IBN Live has reported an ammonia gas leak at Paradeep where 3 workers were rendered unconscious.  The news item mentions that "Sources said some crew members inadvertently handled the gas tank of the ship carrying 13,000 metric tonnes (MT) of ammonia gas meant for the plant. The employees who came in contact with the gas fell unconscious. The unloading of gas through a pipeline to the plant had been completed by then". 
Read the news item in this link.

February 14, 2012

Vehicles and process safety

An incident where a car hit a chemical storage tote has been reported. Ensure you have identified all possible points of impact of vehicles. Piperacks, storage tanks, culverts, loading/unloading stations are all areas which you should study for a possible vehicle collision. I had been to a large refinery which had expanded in the space available. (There was a huge space deficit). Their staff bus had to cut across two units, along a narrow culvert carrying hydrocarbon pipelines. Its a disaster waiting to happen.
Read about the car accident in this link
 

February 12, 2012

Dispersion of chlorine and its containment

Thanks to Harbhajan Singh Seghal for sharing his article on " dispersion of chlorine and its containment". Read it in this link.

February 10, 2012

Management Integrity level (MIL) and Process Safety

There is a lot of talk about safety integrity level and the reliability of control and shutdown systems. While a reliable instrumented system is good for process safety, it is the integrity of management, what I call Management Integrity Level that is more important! By this what I mean is whether management is really interested in process safety by allocating resources, time and competencies. Even if we develop a MIL (Management Integrity Level) rating for management, the score has to be measured and monitored on a continuous basis!
Do not get carried away by SIL ratings and multi coloured QRA's and risk matrices. Look into your organisation and determine whether Management Integrity Levels are adequate! The answer lies within!

February 8, 2012

The dangers of pressure vessels

A good article - Accidents in Pressure Vessels: Hazard Awareness by Temilade Ladokun, Farhad Nabhan and Sara Zarei Mentions the following:  
The main causes of failure of a pressure vessel are as follows:
Faulty Design
Operator error or poor maintenance
Operation above max allowable working pressures
Change of service condition
Over temperature
Safety valve 

Improper installation
Corrosion
Cracking
Welding problems
Erosion
Fatigue
Stress
Improper selection of materials or defects
Low –water condition 
Improper repair of leakage 
Burner failure 
Improper installation

Read the article in this link.

February 6, 2012

New pipeline design concept

DNV has released details of a new concept in subsea pipelines called "X stream". The thickness of the pipe is reduced by using inverted HIPPS concept. It is an interesting read. Read it in this link.

February 3, 2012

Leak detection in sub sea pipelines

An article mentions the use of fiber optics to detect sub sea pipeline leaks based on Joule Thompson effect. Many sub sea pipelines transfer LNG, ammonia etc and any leak in these pipelines will have a catastrophic effect. The article mentions the following: "Fibre Optic Distributed Temperature Sensing (DTS) methods have been successfully applied to many processes in the oil & gas industry. This non-intrusive sensing system proves invaluable in the monitoring of LNG pipelines both for cool down at commissioning, for temperature profiling during operation and as a leak detection system. There is ongoing work in the use of fibre optic DTS systems in the development of smart cryogenic hoses for the transfer of LNG and storage and piping systems aboard floating LNG vessels. Developments in LNG pipes include multi-layer insulated piping systems. This contribution presents recent studies in the use of fibre optic distributed sensors for temperature profiling and leak detection in multi-layer insulated LNG pipes". Read the article in this link.

February 1, 2012

Are your SOP's clear?

There are lessons to learn from an aborted take off recently at Hong Kong airport. The aircraft commenced takeoff not on the assigned runway but parallel taxiway. The air traffic controller noticed the airplane accelerating on the taxiway and ordered the aircraft to stop. There was no other traffic on the taxiway at the time of the serious incident.A news report mentions the following:
"Hong Kong's Civil Aviation Department (CAD) released their final report concluding the probable causes of the incident were:
- A combination of sudden surge in cockpit workload and the difficulties experienced by both the Captain and the First Officer in stowing the EFB computers at a critical point of taxiing shortly before take-off had distracted their attention from the external environment that resulted in a momentary degradation of situation awareness.
- The SOP did not provide a sufficiently robust process for the verification of the departure runway before commencement of the take-off roll.
- The safety defence of having the First Officer and the Relief Pilot to support and monitor the Captain’s taxiing was not sufficiently effective as the Captain was the only person in the cockpit trained for ground taxi'.


Are your SOP's clear and are your operators trained to handle spurts in workload that occur during an emergency?

Read the news article in this link.