Man killed by toxic gas

Author : Amy Hollamby

28 September 2010

Regularly in the news we hear about incidents occurring in the oil and gas, petrochemical and chemical industries which could have been prevented if only basic operational procedures and staff training programmes were in place. This week is no different with crisp-maker Walkers and chemical distributor Omnichem being fined a total of £350,000 after a worker was killed by a cloud of toxic gas.

John Marriott was working for Omnichem on 19 July 2006 when he was seriously affected by green chlorine dioxide fumes. The Health and Safety Executive (HSE), which brought the prosecution, told Leicester Crown Court that Marriott was driving a lorry containing four steel tanks – two of sodium chlorite and two of hydrochloric acid, to Walkers’ Leicester site.

Both chemicals are used in Walkers’ starch reclamation unit, which turns waste starch into food-grade material used to make snack foods. Marriott inadvertently mixed up the hoses on the tanks while transferring the two chemicals from the lorry, causing them to produce green fumes of chlorine dioxide.

When he realised his error, Marriott stopped the transfer and started to hose the area down, but he was already starting to be affected by the toxic gas.

Marriott and a Walkers’ employee who tried to help, were both taken to Leicester Royal Infirmary. The Walkers’ employee was in hospital for 30 hours, with breathing difficulties, but later recovered. Marriott’s condition gradually deteriorated, and he died from the effects of the gas a month later on 17 August 2006.

Walkers Snack Foods, of Arlington Business Park, Theale, Reading, Berkshire, pleaded guilty to breaching Sections 2(1) and 3(1) of the Health and Safety at Work etc Act 1974 and was fined £200,000. It was also ordered to pay costs of £38,971. Omnichem admitted the same charges and was fined £150,000 and ordered to pay £29,229 costs.

HSE inspector Sue Thompson said: "This incident was entirely preventable. Basic risk assessments and clear procedures could have avoided Mr Marriott’s tragic death but as it was there were a catalogue of serious failings.

"Employees who had tried to help Mr Marriott did not know the type of operation that was being carried out, nor the nature of the gas being released. They had no appropriate training and they had no idea what to do.

"It took about an hour after the appearance of the gas cloud for Walkers to realise the gravity of matters, and to get employees out of the area. Walkers had no planned evacuation procedure for a chemical emergency at this location, which was a major failing.

"There were insufficient written procedures for deliveries of chemicals and for the receipt of chemicals, and the tanks were also insufficiently labelled."

Following the incident, Walkers put in place emergency procedures to deal with chemical incidents. It also eliminated the potential for the tank hoses to be mixed up by introducing a system so that only one chemical is delivered at one time. Omnichem audited its procedures and has since made them more robust, as well as committing to undertake site-specific risk assessments when delivering chemicals.

This incident highlights that many companies seem to have a reactive response, and only start to take notice of health and safety requirements after an incident occurs. However, this is too late and it is often the case that lives have been lost. Companies need to adopt a more proactive approach to health and safety to avoid repeating the same mistakes of other companies before them.

READER'S VIEW
From:Andrew J Brown
Approvals Engineer, Radiodetection

Having just read about the Walkers incident I have a comment to make.
I previously worked for Ishida, supplying weighing equipment to Walkers and what does surprise me about the incident is that Walkers really do take their site safety seriously, particularly for site visitors / suppliers. Sometimes it would even appear to be "over the top" but this did reflect their excellent safety record.
I guess what I am saying is that if a company such as Walkers can get it wrong, any company can and this is an alarm bell to other companies not to get complacent.

From:Peter How
CMIOSH, MIFE, MIEE, C.Eng, Consultant

What Andrew may have seen is a company concentration on "hard hat" safety, where they home in on the physical asspects of safety, but forget to examine "process safety" where the risks may not be obvious, but these chemical or process deviations can cause horrors & injury to people..

From:Trevor Best

Remember the Camelford Incident when mains water was contaminated because of a mix up by an aluminium fluid tanker driver when connecting a tanker pipe to the wrong inlet of a water treatment process? Since then the pipe connectors have been changed so that the wrong connection cannot be made. It seems that Walkers should have adopted the same principle. The question to be asked is why there is no specific and obvious safety ruling to create a fool proof method to avoid this happening in the first place. The other more sinister aspect is that Camelford was 22 years ago and current driver/operatives were very young or not born then so they would not be aware of automatic memory based precautions in handling diverse chemicals. To finish there is also the "custom and practice" rule and I am willing to bet that the driver had carried out this unloading procedure many times the wrong way without incident.