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.

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.

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
 

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.

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!

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.

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.

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.

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.

Chlorine tonner incident

Thanks to Mr Harbhajan Singh Seghal for sending this incident:
INCIDENT
In one of the chlorine consuming industry two persons were affected with chlorine while the operator disconnected the tonner from the process due to hard valve operation of the tonner.
DETAILS OF INCIDENT
· The consumer withdraws liquid chlorine from the chlorine tonner and consumes gas after evaporation.
· As per practice, the consumer keeps the tonner in line to withdraw maximum chlorine from the tonner.
· On the specific day of the incident, the operator tried to isolate the tonner at 1.0kg/cm2 pressure when about 40-50 kgs liquid chlorine was left in the tonner and there was ice formation at the bottom of the tonner.
· He could not close the valve fully. The spindle of the valve damaged due to excessive force.
· The operator decided to cut off the tonner by wearing SCBA.
· This action resulted in heavy gas leakage and affected two persons in the surrounding area.
ACTION TAKEN
· The tonner brought to the works.(of the chlorine supplier)
· It was depressurized and the valve was dismantled
· Iron chloride rust and greenish color sludge was observed in the threading of the valve.
· Damaged valve replaced with new valve.
ROOT CAUSE
· Liquid chlorine withdrawal rate is 180 kgs/hr. Maximum liquid chlorine is used up in 4-5 hrs operation at this rate. Some quantity (40-50) kgs remains in the tonner at the bottom.
· Some consumers try to recover this 40-50 kg liquid chlorine as gas by keeping the tonner in line for more time.
· The left over liquid chlorine evaporates at 5-6 kgs/hr as gas and lowers the temperature of the tonner/pipe lines due to fall in pressure till the remaining liquid chlorine is exhausted.
· 1.0 kg/cm2 pressure can lead to about -20 degree C and takes 8-10 hrs to completely empty the tonner.
· Normally chlorine in the tonner is dry. But under such conditions (-200) the same chlorine becomes wet.
· Water in the chlorine separates out and freezes in the spindle of the chlorine valve. It makes the valve hard to operate at that time.
· After attaining normal temperature, chlorine evaporates first and water later. This chlorinated water reacts with the sprindle and makes the chlorine spindle greenish.
· The evaporators which do not have backflow prevention system (from evaporator to chlorine tonner) results carry over of iron chloride rust to valve spindle and makes the valve hard in operation.
LESSONS LEARNT
· The tonners containing some quantity of liquid chlorine (40-50 Kg) are not to be cut off at 1.0kg/cm2. The tonner is to be depressurized by releasing the chlorine to neutralization system through header or evaporator.
· After depressurizing, check that no chlorine gas comes from the upper valve of the tonner, and also check that no ice formation appears on tonner or pipe lines before the tonner is disconnected.
· Chlorine header and evaporator must have chlorine release facility connected to neutralization system.
· Chlorine evaporator must have liquid chlorine flow control interlocked with temperature and outlet pressure to avoid the back flow of chlorine
· Evaporator should have emergency release system with rupture disc and safety valve.
· Temperature of evaporator should be maintained between 80-85 degree C to avoid formation of rust as Fecl3 in the evaporator.
· Dry air (-40 degree) dew point is to be utilized for evaporator maintenance.
· Glass wool filter is to be utilized in gas line to avoid carry over of Fecl3 to main products and choking in chlorine system.
· Tonners can be kept in tilted position forming 20-30 degree angle to withdraw maximum liquid chlorine from the tonner.
MOST IMPORTANT LESSONS
· No chance should be taken with liquid chlorine system. Help of the filler (chlorine supplier) must be taken in such cases. One volume of liquid chlorine expands to 460 times
· Chlorine neutralization system must be effective and checked from time to time.
· Single person should never take this type of emergency job.
· Always stand by person ready with safety equipments should be present during such operations.

Process safety - Seeing and managing

A typical day for today's plant manager is like this: Punch in....login......read emails and answer......collect data for the meetings scheduled......firefight today's issues.......go back home late in the evening! I was just comparing the daily routine i used to do many years ago in the same position: Punch in....go around the plant for at least one hour.......read the log book.....write relevant instructions in the instruction book.....attend the daily plant meeting for discussing and resolving issues....discuss and take instructions from my boss....communicate these instructions to the plant......go back home peacefully, on time! Note: There were no ISO9000,ISO14000,OHSAS18001,PSM,TQM,Six sigma etc in those days! Managing process safety needs management by seeing, hearing and understanding. Unfortunately today's plant managers do not have the time to see the plant.....this is a dangerous trend. Also competency for managing process safety is lacking. Somewhere we seem to have lost our way!

Awards and Accidents

Further to the refinery accident during hot work which I had mentioned in my previous blog entry, an article in the Hindu lists out other accidents that occurred in the same refinery in 2009. It also mentions that the refinery won safety awards in 2009 and 2010. There is a disconnect here! Read the article in this link.
While awards are a good way to motivate people, the onus lies on management to sustain and improve process safety performance.Long ago, I had audited an organization that had been granted a prestigious award by an international organization for their safety management system. I visited the plant 6 months after this award. Their safety management was in shambles and I had mentioned to them that the sword is now hanging over your heads.
If everyone goes back home safely everyday and this is maintained, then your process safety management system is working well! Period.