Mike Everley reports on a breach of the Dangerous Substances and Explosive Atmospheres Regulations 2002.

A company was fined £20,000 with £6860 costs, after making an early guilty plea to breaching regulation 6(1) of the Dangerous Substances and Explosive Atmospheres Regulations 2002 (DSEAR). The prosecution followed a decanting operation at the company’s premises resulting in a fireball that ignited and engulfed an industrial estate.

Background

The process that was taking place at the time of the blaze involved making a blend mix and transferring the solvent toluene from an intermediate bulk container into 2 smaller drums containing 205 litres each. The operation relied on gravity feed, as the intermediate bulk container was lifted by a fork-lift truck into the air where a metal pipe was attached to the tap at the bottom of the container. The other end of this pipe was subsequently positioned over the hole at the top of each of the drums.

Although earthing straps were connected to the bulk container and the drums, they were not attached to the metal pipe. The first drum was filled successfully, but halfway through filling the second drum, the employee involved in the process saw some flames and turned off the tap. He then tried to tackle the fire using an extinguisher until his supervisor evacuated the site of all its seven workers.

The flash point of toluene is 4°C and, on the hot summer’s evening when the operation was being carried out, the liquid would have released a flammable vapour over its surface susceptible to the static electrical charge thought to have provided the ignition source.

This initial fire quickly spread to the other containers of flammable solvents and mixtures on the site, some of which then exploded. The time it took for the initial fire to become a raging inferno was only a few minutes. CCTV footage from a neighbouring company revealed that 30 seconds after the first sign of smoke there was a major plume and 60 seconds later a massive fireball, with tanks flying into the air. This reinforces the point that fires involving flammable vapours can develop and spread very quickly, and robust emergency procedures and control measures need to be in place.

Statutory requirements

DSEAR defines a “dangerous substance” as:

  • a substance or preparation that meets the criteria in the approved classification and labelling guide for classification as a substance or preparation which is explosive, oxidising, extremely flammable, highly flammable or flammable, whether or not that substance or preparation is classified under the Chemicals (Hazard Information and Packaging for Supply) Regulations 2009

  • a substance or preparation that, because of its physico-chemical or chemical properties and the way it is used or is present at the workplace, creates a risk

  • any dust, whether in the form of solid particles or fibrous materials or otherwise, that can form an explosive mixture with air or an explosive atmosphere.

Regulation 6(1) of DSEAR requires that every employer must ensure that risk is either eliminated or reduced, so far as is reasonably practicable. Given the cost of providing a longer pipe, better earthing arrangements and anti-static personal protective equipment (PPE), this was obviously reasonably practicable given the nature and scale of the risks involved in the decanting operation.

Other breaches of DSEAR that were applicable, but not used in the prosecution include the following.

  • Breach of regulation 5(1), which requires employers to carry out a suitable and sufficient risk assessment where a dangerous substance is or is liable to be present at the workplace. Regulation 5(2) specifies the factors to be considered in the assessment and these include: the hazardous properties of the substance, any information on safety provided by the suppliers, and the circumstances of the work. Where five or more people are employed, the significant findings of the assessment need to be recorded and the assessment should be subject to regular review.

  • Breach of regulation 6(3), which requires employers, where it is not reasonably practicable to eliminate risk, to, so far as is reasonably practicable, apply measures consistent with the risk assessment, and appropriate to the nature of the activity or operation, to control risk and to mitigate the detrimental effects of a fire or explosion or any other harmful physical effects arising from dangerous substances. Regulations 6(4) and 6(5) then list a series of measures that can be taken in order to control risks or mitigate effects.

Failings

Apart from the metal pipe not being earthed and bonded to the bulk container and the drums being filled, it was also too short and, as a result, the liquid had to be dropped into the drums rather than being filled from the bottom of the drums. Such “splash filling” is also known to generate static electricity. According to the Health and Safety Executive (HSE), the method of splash filling was inappropriate for this process and posed a clear risk that was not properly assessed.

The use of a longer filling pipe, along with better earthing arrangements, were reasonably practicable measures to take, particularly as the company was well aware of the dangers of splash filling following HSE written advice toit, given on two occasions, several years earlier. In response, the company had assured HSE that anti-static PPE would be provided. One could criticise HSE for not taking firmer action at this stage as the company should have considered dealing with the risk at source by changing the method used for the decanting operation.

In addition, although the company’s policy required employees to wear anti-static clothing and footwear, it was not worn on this occasion. Finally, the operation did not take place in a bunded area and, if it had done so, the spillage would not have spread so easily around the site.

Lessons learned

Although the company entered an early guilty plea, the judge did not discount the maximum fine that he imposed, saying that he was unhappy that the company had not acted upon the previous advice that it received.

Had the supervisor not acted quickly in evacuating the site and notifying the emergency services, several lives could have been lost given the speed and intensity with which the fire developed. The HSE inspector involved stated: “The workforce were extremely lucky to escape unharmed from this incident. The size and scale of the fire was immense; it took hold in minutes and caused total devastation of the company’s premises. Lives were needlessly put at risk because there would have been no blaze at all had the company taken more care with the decanting operation.”

In mitigation, the company claimed to have co-operated with the HSE investigation into the incident and liaised closely with it concerning the design of the safety features during the rebuild of the factory.

The main lesson to be learned is that companies working with dangerous substances, such as flammable solvents, must take extreme care at all times, or face potentially devastating consequences.

Last reviewed 9 January 2013