Sub-contracted labour exposed to asbestos

All contractors now labour, reluctantly it has to be added, under a mound of paperwork designed to ensure that they are competent and adequately resourced for safety.  We hear many grumbles about the level of checks required but every now and then a case gives rise to a good reason for all of this to be in place.

In this case a company called Gardner Mechanical Services Ltd had been contracted to undertake some alterations at Reading University. GMS then sub-contracted the mechanical services project to another company, which in turn sub-contracted the work to two self-employed workers. On September 2 2009 the two men drilled through a sprayed asbestos coating which was applied to a ceiling exposing themselves to significant levels of asbestos fibres and putting themselves at risk of later contracting a fatal disease such as lung cancer or mesothelioma.

On inspection, HSE found that the two workers had not been made aware of the presence of asbestos. GMS had been made waware that there were asbestos-containing materials present in the building but did not pass on the information to the sub-contractors in a reliable way.

GMS pleaded guilty to breaching the Control of Asbestos Regulations 2006 by allowing the workers to be exposed to the fibres. It also pleaded guilty to breaching Regulation 23(1)(a) of the Construction (Design and Management) Regulations 2007 (CDM) as there was no suitable construction phase plan to ensure that the work could be carried out without risk. The firm was fined £28,000 and ordered to pay £22,631 in costs.

Affect on the client

The University was found to have handed over sufficient information to enable the work to be done safely. However, as principal contractor GMS had a key responsibility which it plainly failed to discharge. A project of this scale is classed as “notifiable” under the CDM Regulations 2007 and required a Construction Phase Safety Plan and CDM Coordinator to be in place.  Because of this the location of asbestos-containing materials should have been clearly written in the  plan. To comply with CDM this plan would have to have been in place before the first day of work on site and made available to any sub-contractors.

Risk of carbon monoxide release during the storage of wood pellets

We have seen numerous incidents in which carbon monoxide has caused death in both commercial and domestic situations. This silent killer cannot be smelt to seen but creeps into homes and kills through preventing the normal uptake of oxygen in our blood.

What we did not know up to now was how it can build up through natural means in storage areas used for wood pellets.  These boilers are becoming more and more common in large or shared domestic and also commercial applications, the information from HSE below provides more information on how this occurs and what you can do to manage and control the risk.

Health and Safety Executive – Safety Notice
Department Name: Operational Strategy Division – Manufacturing Sector (General Manufacturing Team)
Bulletin No: OPSTD 3-2012
Issue Date: 5 November 2012
Target Audience:
  1. Users/installers/maintainers/distributors of wood pellet boilers
  2. Manufacturers/storers/distributors of wood pellets
Key Issues: Storage of wood pellets: Risk of death from carbon monoxide

The HSE is issuing this notice to those who use, install, maintain or distribute wood pellet boilers or manufacture/store/distribute wood pellets. Since 2002 there have been at least nine fatalities in Europe caused by carbon monoxide poisoning following entry into wood pellet storage areas. Although there have not been any incidents so far in the UK the use of wood pellets is increasing and awareness of this danger is required. Wood pellet boilers are used in homes and businesses as an alternative to oil or gas fired boilers. They are also being installed to replace coal-fired boilers, particularly in schools.

Carbon monoxide can kill quickly without warning. It is a colourless, odourless and tasteless gas that is highly toxic. When carbon monoxide enters the body, it prevents the blood from bringing oxygen to cells, tissues, and organs.


Wood pellets are made from dried and milled sawdust and wood shavings that have been compressed into pellets, typically 10-20mm long and 3-12mm in diameter. They do not typically contain any additives or binders.

They are classed as a biofuel, a non-fossil heating fuel. The main countries of manufacture are Canada, North America and the Scandinavian countries within Europe. In 2000, the annual production of wood pellets in Europe and North America was about 1.5 million tons. This was expected to increase to around 16 million tons by 20111. Some wood pellet manufacture is now taking place in the UK.

Fatality details:

Fatalities caused by the release of carbon monoxide from wood pellets have previously been reported2 in Europe following personnel entering ships cargo holds (four) or storage silos (two).

Since 2010 there have also been three deaths caused by entry into wood pellet storage facilities in domestic sites3. Two were associated with a work activity and the other was a householder. In each case, the entry had been to resolve a technical problem. Details:

  • In January 2010, a 43-year-old engineer died in Germany after he opened a pellet bunker door. A second worker who was standing right behind him was also affected but still able to call the emergency services. The pellet bunker had a storage capacity of approximately 155 tonnes of pellets, supplying about 700 households.
  • In November 2010 a 38-year-old male householder in Ireland died after entering the 7 tonne wood pellet storage room for his boiler. His wife and another man were treated in hospital after trying to pull him to safety.
  • In February 2011, the 28-year-old pregnant wife of a caretaker, acting on his behalf, died in Switzerland after entering an 82m3 pellet storeroom that supplied 60 households.

Factors affecting the amount of carbon monoxide released from wood pellets

Wood pellets for boilers are normally stored in a large sealed hopper/tank or a storage room that has a screw feeder (auger) connected to the boiler. Alternatively, the hopper/tank can be mounted over the boiler for gravity feeding. Due to the enclosed nature of these hoppers/tanks/rooms, the atmosphere inside can become oxygen depleted and a toxic atmosphere containing carbon monoxide can accumulate. The chemical reactions responsible for carbon monoxide production from wood pellets are assumed to be an auto-oxidation process, especially oxidation of the fatty acids to be found in wood4.

Experimentation has shown3 that small quantities of wood pellets can produce life-threatening quantities of carbon monoxide in a confined space and that there are various factors that will affect the amount of carbon monoxide produced:

  • Age – pellets will produce more carbon monoxide within the first six weeks of being manufactured.
  • Temperature – more carbon monoxide is produced at higher temperatures.
  • Wood type – pellets made from pine contain more unsaturated fatty acids than spruce so produce more carbon monoxide.
  • Other factors – carbon monoxide levels will also increase with the amount of available oxygen present, exposed pellet surface area and amount of mechanical abrasion of the pellets that has taken place.

Note: In addition to the risk of carbon monoxide from wood pellets there is also a possibility of carbon monoxide being present because of a back-flow of flue gases via the fuel supply mechanism from the boiler. Causes for this include inadequate equipment being installed or a poorly designed flue.

Action required:

The HSE is advising all those who use, install, maintain or distribute wood pellet boilers and/or manufacture/store/distribute wood pellets to consider the following:

  • Wood pellet hoppers/tanks/storage rooms and boilers should always be installed and commissioned by a competent person, normally approved by the manufacturer/supplier. This is particularly important if the installation involves the replacement of a coal-fired boiler, where existing boiler room and storerooms are often utilised.
  • Do not enter the pellet storage area or place your head into a wood pellet hopper as they can contain toxic gases. No personnel should enter the hopper/tank unless fully trained and competent in confined space entry procedures. Controls should be put in place to ensure safe entry as per the HSE’s Code of Practice for Working in Confined Spaces5. This should include adequately ventilating the storage area and checking carbon monoxide and oxygen levels with an appropriate device prior to entry. It is recommended that the store room is ventilated at all times, either mechanically or by being designed to have a through draft.
  • Ensure that the boiler and pellet feed mechanism etc. is cleaned and serviced by a competent person as specified by the manufacturers’ instructions.
  • If any problems are encountered with the unit, such as the system not heating correctly or flue gas is flowing into the boiler room, turn the unit off and contact the supplier and/or manufacturer and request assistance.
  • Duty holders who store wood pellets, particularly in bulk should have a suitable risk assessment and safe system of work in place.
  • Manufacturers, suppliers and distributors of wood pellets should provide adequate health and safety information to the user in their materials safety data sheet.
  • Warning signs should be placed on the pellet storage area access door, ideally on both sides so it can be seen when the door is open. The warning sign should include the following information:
    • DANGER – RISK OF CARBON MONOXIDE POISONING – There is a danger to life from odourless carbon monoxide and lack of oxygen. Check atmosphere before entry with an appropriate device. No entry for unauthorised persons. Keep children away from the storeroom.
    • No smoking, fires or naked flames.
    • The room should be adequately ventilated before entering. Keep the door open whilst inside.
    • There is a danger of injury from movable parts.
    • Filling procedures should be carried out accordance to the instructions of the heating installation company and the pellet suppliers.

Worker left unconscious after garage oil-drum explosion

A repair-garage workshop assistant was knocked unconscious by an oil drum exploding after an oxyacetylene torch was used to cut it.

CCTV footage of the blast (see link below) showed the worker being knocked backwards, the drum shooting up into the air, and his colleagues rushing to extinguish the ensuing fire. He remained unconscious in hospital for five days following the explosion.

Video of blast

The magistrates fined CVS (Anglia) the maximum penalty of £20,000 on each of two charges after it pleaded guilty to breaching s2(1) of the HSWA 1974 by not ensuring its employees’ safety and reg. 3(1)of the Management of Health and Safety at Work Regulations 1999 by failing to conduct a suitable risk assessment of the potential danger.

Nigel Burrows, the investigating officer from Ipswich Borough Council, who brought the prosecution, commented;

“The maximum £20,000 fine on each charge is very significant, as it shows the seriousness of the incident and should act as a deterrent to other duty-holders,” said .

CVS, which employs around 15 people, had a history of cutting off the ends of disused oil drums to make waste bins.  The company expressed genuine regret for the incident and said in mitigation that the owner was not at the garage on the day of the incident. The oil-drum modification did not form part of normal work activities and so the firm did not believe a risk assessment was necessary. However, Burrows said the firm had failed to produce any risk assessments for the use of oxyacetylene-based equipment at its premises.

Councillor Neil Macdonald, deputy leader of Ipswich Borough Council, commented:

“The injuries to Mr Gavin were serious, but given the circumstances there could well have been a fatality. We are relieved that Mr Findlay has made a good recovery, that no one else was injured by the explosion, and that it did not result in the premises catching fire.

“We hope this sends a strong message to those businesses not complying with their duties to protect their staff and also that this raises awareness of how dangerous workplaces can be if not properly managed.”

As well as the £40,000 fine, full costs of £16,963 were awarded against CVS (Anglia).

We’re working with HSE and many major construction partners including Kier and ISG

We’re working with HSE and many major construction partners on the South West Working Well Together Campaign.  This event is aimed at contractors and developers within smaller businesses employing 1-15 staff, please take a look through the information below and click the link to book your place on this event.  If you are a larger contractor your sub contractors should attend this key event.

WWT Event Cheltenham Racecourse February 26th 2013

Fitness for Work – Fitness for Life

Sales Arena & Betting Hall. CHELTENHAM RACE COURSE

This free half day event is the perfect opportunity for you to gain a better understanding of some key health and safety responsibilities and how to safeguard the health and well-being of you, your workforce and your business.

On the 26th February at Cheltenham Race Course construction industry experts will be on hand to offer guidance and advice on:

  • Asbestos awareness
  • Silica dust
  • Facefit testing
  • Handarm vibration
  • Noise in construction
  • Welfare

 To book a place at our event please download the event information document here.   

For any other enquires please email