Speaker: Eddie Kalinowski, Health, Safety & Environment Manager, Dugdale PVC, Sowerby Bridge

Date: 15 March 2018

Eddie started his presentation with a slightly different interpretation of the COSHH acronym: Chemicals Often Sting Hurt and Harm you to help people understand the need for the Control Of Substances Hazardous to Health Regulations.

He then compared the complex HSE definition of hazardous substances with the Wikipedia definition; members agreed that the later was more helpful. It says:

“…Hazardous substances, are solids, liquids, or gases that can harm people…”

Eddie explained that people often interpreted the need for COSHH assessments in an arduous, complex way that required individual COSHH assessments for every substance used. He suggested that this resulted in poor communication of important information to employees and tradesmen, and a poor understanding of the potential risks that they posed by those using COSHH substances in the workplace.

He then listed some common short-comings with COSHH assessments:

  • They concentrate on hazards of individual substances rather than looking at the risks that they pose when used during a specific task.
  • They neglect substances that are generated by the task such as fine dusts.
  • They lack emphasis on control measures that contain the risks when used correctly.

He suggested that over-emphasis on Material Safety Data Sheets, now known as Safety Data Sheets (SDS) was one of the reasons why some COSHH assessments became over- complex. He recommended that these sheets should be used in conjunction with pictograms on substance labels, CLP Regulations, EH40 Exposure limits and personal knowledge and experience.

He said that Safety Data Sheets were only a guide to potential hazards which is why data sheets from different manufacturers of the same substance are not identical and he reminded members that some substances, created as a by-product of the task, often do not have safety data sheets. Eddie also reminded members that potential hazards and risks are not limited to substances labelled as hazardous.

Eddie explained that COSHH assessments can be divided into two main types:

  • Substance based – focus on one substance use and/or its generic use.
  • Task Based  – refer to multiple substances, detailing the task being carried out step by step.

He used COSHH assessments for paint spraying to explain the difference between these two types of assessments. He showed that the eight constituents of the spray paint could be broken down into three groups: resins, solvent carriers and pigments with three potential hazards – flammable, irritant and may cause sensitisation.

Once the potential hazards have been identified Eddie explained that it is then necessary to identify the risks posed by the way the substances will be used where:

RISK = Likelihood x Consequences

Likelihood is dependent on control measures/systems of work.

Consequences is the injury caused.

Eddie said the crucial part of COSHH assessments for hazardous substances is to assess:

  • Quantity used
  • Concentration used and
  • Duration (time taken to use the substance while undertaking the task)

He explained that the potential risk(s), from the same hazardous substances, can vary because different tasks require the use of different quantities and concentrations of the substance and they have different exposure times. For instance:

Quantity:  The amount of material used, or to which the employee is exposed, can change the COSHH risk factor. For example, the use of large volumes of a hazardous substance, in small spaces, might have catastrophic consequences, whereas, the use of small volumes of the same substance, in a large space, might pose a negligible risk.

Concentration:   The concentration levels of the hazardous substance affect the COSHH risk factor. The more concentrated the hazardous substance is the higher the exposure risk becomes therefore the use of very dilute solutions of the hazardous substance may only pose a negligible risk to employees undertaking a specific task.

Eddie gave members a generalised ‘rule of thumb’ for assessing potential likelihood of a high risk factor using Quantity and Concentrations as yardsticks:

HIGH RISK: use of High Concentrations of a hazardous substance in Large Quantities.

Reduced risk: use of Low Concentrations of a hazardous substance in in Large Quantities.

Reduced risk: use of High Concentrations of a hazardous substance in Small Quantities

Negligible risk: use of Low Concentrations of a hazardous substance in Small Quantities.

He said that the time (duration) that it took workers to complete their task, using a hazardous substance, was also an important consideration and should be considered alongside quantity and concentration. He illustrated this point by saying that the time that you spend in a pub can have a marked effect on the state you are in when you leave!

Eddie reminded members that it was important to communicate the content of COSHH assessments to those undertaking tasks using hazardous substances and to provide appropriate training and supervision.

Eddie used some example COSHH assessments to illustrate the COSHH assessment process that he found most useful. He said that he believed that there were occasions when a ‘suitable and sufficient’ COSHH assessment could be included as part of a wider task Risk Assessment. Similarly, he suggested that there were occasions when a substance based COSHH assessment is likely to be more appropriate than a task based COSHH assessment, for example when using very toxic materials, biological materials and known carcinogens.

There was also some interesting discussion about whether things such as: Spillage Procedures, First Aid Procedures, Fire Fighting Procedures, Emergency Procedures etc… should be included in COSHH assessments. It was agreed that there was no ‘right’ or ‘wrong’ answer to this although the general feeling was that these were normally more appropriately dealt with as separate procedures that were referenced in COSHH and Risk Assessments.

Eddie’s presentation generated some lively discussions and was much appreciated by members attending the meeting.

A copy of Eddie’s presentation is available here: March 2018 COSHH – focusing on Quantity Concentration and Duration






COSHH: helping SMEs by focusing on Quantity, Concentration and Duration