Select suitable sorbent
April 1st 2007

Liquid oil and chemical spills are normally viewed in the light of their environmental consequences with little regard to safety hazards. Now, triggered by indications that the incidence of dermatitis and adverse effects of handling chemicals are increasing, and the fact that while there are Oil Storage Regulations, other liquids are purely covered by COSHH, the BSIF Sorbent Manufacturers' Group is seeking to bring a wider awareness of the hazards associated with liquid spills and the subsequent disposal of waste. Miles Hillman comments

It is not easy to identify the number of incidents each year as the majority of data available is not categorised as 'caused by spill handling'. There is little doubt that many of the reported dermatological incidents are as a result of the handling of spills and the disposal of the waste. It is also highly probable that injury and harm caused by 'chemicals' will be as a result of spills and not regular handling. Without this information it is difficult to target solutions.

Nevertheless, there are some general good practice principles that should be included in the risk analysis and design of the procedures to deal with these spills. Also, there is now much improved guidance on the selection of suitable Sorbents.

There are three major safety elements affecting liquid spills: Spills are generally handled by staff in 'emergency' situations; the incorrect selection of a suitable sorbent can be seriously damaging; the information in most COSHH material data-sheets provided by suppliers is inadequate when it comes to dealing with spills.

The BSIF Sorbent Manufacturers' Group has addressed the first major safety hazard by introducing an accreditation scheme for the training of first responders.

In general, sorbents are classified as 'oil-selective', 'chemical', and 'maintenance'. The new Guidance on the Selection for Use of Sorbent products, published by the BSIF and produced in conjunction with the Environment Agency, should help in deciding which sorbent should be used by matching it to the spilled liquid. As sorbents come in a variety of physical forms and the areas where the spill takes place could also vary, this Selection Guidance seeks to provide additional information to help selection of the correct form and type of sorbent.

Oil specific sorbents will not take-up water and aqueousbased materials. This gives the benefit of being able to extract oil floating on water but has the inherent danger that if used on an aqueous spill, it will not work and could exacerbate the problem by spreading the liquid. If the liquid is in itself hazardous, this presents problems to those dealing with the spill and disposing of the waste.

Most general purpose and chemical sorbents will take-up both oils and water-based materials. It does not take a genius to realise that if the material is oil-based and the spill is in wet conditions, the take-up of the oil-based material will be reduced by the amount of water taken up, significantly reducing the effective performance of selected sorbent to take-up an oil-based material. The advice here is clear: know and understand the materials that are in use and likely to be spilt and select the most appropriate sorbents to handle them and always consult COSHH materials data sheets.

Historically, sawdust, sand or earth have been used to mop-up liquid spills. These are poor sorbents and their inappropriate use, for example with nitric acid, could be seriously dangerous and may even create fires.

The Colour Coding set out in BS 7959 part 3 should help sorbent selection. Developed by the BSIF in conjunction with the Fire Services and the Environment Agency, it is designed to ensure instant recognition of the differences between the three types of sorbent (note, not all manufacturers use this colour code standard and specifiers should be careful if using this colour code to select and identify sorbent types when the BSIF logo is not evident). The BSIF is currently lobbying for this standard to be mandatory.

Closely connected with the selection of suitable sorbents is the need to ensure that adequate supplies are available close to the location where chemicals and other hazardous liquids are stored and used. Many manufacturers of sorbents use spurious test methods and 'beneficial' challenge materials to establish their published performance information – the best advice is to ask the supplier to identify the performance of the sorbent with the liquids you are using. You will have little chance of ensuring adequate supplies of sorbent if the quantity is based on over-egged performance data.

The law is no help here as this is an unregulated area and manufacturers can make any claims they like providing they can evidence how they have achieved them. Always check or ask for evidence that the information provided has been obtained using the British Standard 7959 test method. Membership of the BSIF Sorbent Manufacturers Group is dependant on these companies agreeing to use BS 7959 to test their product performances.

Apart from the emergency services and the Coastguard Agency, industrial liquid spills will usually be handled in emergency situations by staff who only apply their knowledge and skill under stress and, despite practice sessions, may not be ideally experienced. This is primarily because they are not called on to handle these situations on a regular basis. Many members within the BSIF Group provide training for 'first responders to liquid spills'. The BSIF accredits these courses, providing a 'qualify mark' to the providers to ensure consistency and quality.

The somewhat loose advice in many COSHH Material Data Sheets contributes to the likelihood of people being harmed. If the information is inadequate for your purpose and you are unable to stimulate your supplier to provide better information, we at the BSIF would welcome being advised. While we will not be able to provide the specific information you are seeking, we may be able to influence the law-makers to insist that suppliers provide more accurate and succinct information in the future. Apart from the Oil Storage regulations, only the general COSHH regulations will apply and there is, therefore, little focus on this hazard in most premises handling process solvents, chemicals, lubricants and oils.

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