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Section 8: Exposure Controls and Personal Protection
In Section 8, the suppliers will provide you with information which, when considered in conjunction with your premises and the task, will assist you in determining the limits of exposure for this substance. Once you know the exposure limits, you'll be able to select control measures sufficient to limit exposure to within those limits.
8.1. Control Parameters
Derived No-Effect Level (DNEL)or Derived Minimal-Effect Level (DMEL)
DNEL: The level of exposure to a substance at which humans should not be exposed. Manufacturers and importers of chemical substances are required to calculate DNELs as a part of their chemical safety assessment for any chemicals used in quantities of 10 tonnes or more per year.
Substances: DNELs are reported for substance and should be harmonised by all registrants. Each substance should only be assigned one set of DNELs. This information is available publicly, even for those who did not register their substances.
Mixtures: DNELs for mixture are reported the hazardous components, and as such, it is normal to see multiple DNELs provided. Authors of SDS for mixtures can be selective and may choose to report only those DNELs which are contributing to the hazard from dermal, inhalation or ingestion exposure.
DMEL: Very similar to DNELs, except to ensure minimal effect due to there being no No Observed Effect Level (NOAEL) when testing on animals.
Predicted No-Effect Concentration (PNEC)
The concentration of a chemical which marks the limit at which below no adverse effects of exposure in an ecosystem are measured.
PNEC values are intended to be conservative and predict the concentration at which a chemical will likely have no toxic. The exposure scenarios contained in an extended safety data sheet should provide advice to help users of the product keep exposure to below the predicted no-effect levels.
Exposure Scenarios (ES)
Most of the information required to ensure the correct controls are implemented can be found in the exposure scenarios of an extended safety data sheet. The supplier should provide several scenarios of exposure relating to their product.
National and European Exposure Limits
The supplier may provide information relating to both National (UK) and European (harmonised) occupational exposure limits for chemical substances, and exposure limits for each hazardous components in the mixture.
Exposure limits are generally calculated for personal exposure, meaning samples are taken from the personal air space. However, it is important to take any static or workplace samples into account. They can highlight specific engineering controls which may be required.
Please note: Any air sampling must be undertaken by someone with the relevant training (e.g. an occupational hygienist).
Workplace Exposure Limits (WELs)
Occupational exposure limits are generally presented as a workplace exposure limit and are associated with hazardous chemicals which the product is a vapour, is capable of producing vapours, or is capable of producing dust during use.
There are two types of WEL which may be included in the safety data sheet:
Short-Term Exposure Limit: The maximum concentration of a chemical to which workers may be exposed continuously for up to 15 minutes without danger to health or work efficiency and safety.
Long-Term Exposure Limits: An occupational exposure limit covering prolonged exposure. LTELs are usually quoted over an 8-hour time-weighted average (TWA) reference period.
Whichever WEL the supplier includes, it should be quoted from the latest edition of the HSE's EH40 Workplace Exposure Limits publication.
Please note: The SDS may contain exposure limits from another country. You can find a glossary of definitions right here.
However, this information may not always be available. In this case, the supplier may include their own exposure limits, usually derived from in-house testing results. If the supplier has provided their own exposure limits, ensure you contact them for clarification.
8.2. Exposure Controls
The extent you need to go to to protect against exposure will depend on the properties and hazards inherent in the product, the amount of it you using and the actual task being performed. To work this out you need to understand the safety data sheet - including the exposure limits and conduct a risk assessment.
Please note: You should never take the information given in this section as an absolute. Every company works under different circumstances. Ensure risk assessments are taken - taking into account each route of exposure - to ensure exposure protection is sufficient.
Your risk assessment, along with the information provided by the supplier in the safety data sheet, will tell you which exposure controls you need to implement.
Engineering Controls
The use of engineering controls is very common in the workplace, so in Section 8 it is likely you will find the recommendations provided by the supplier.
They should advise on specific methods or mechanical equipment to implement to ensure exposure is reduced to below the minimum threshold for that particular product.
The supplier will generally suggest:
Ventilation:
Natural: Opening specific windows to increase airflow through the building.
Mechanical: Installing a local exhaust ventilation system close to the source of exposure to forcefully remove contaminated air from the area.
Please note: Mechanical ventilation is a specialist area and should only be done by someone with the relevant training (e.g. knowledge of capture velocity).
8.3. Personal Protective Equipment (PPE)
It is the case - more often than not - that engineering or mechanical control cannot be used. The controls may not be sufficient, or it may not be reasonably practicable to install local exhaust ventilation throughout the warehouse as well as the work area.
The supplier may advise you to provide any of the following:
Protective clothing:
Chemical-resistant clothing.
Protective shirts, t-shirts, sweatshirts.
Work trousers, overalls, underwear.
Hi-visibility clothing.
Heat and flame resistant clothing.
Work jackets and coats.
Protective work and safety gloves:
Rigger gloves.
Grip glove.
Thermal gloves.
Nitrile gloves.
Criss-cross gloves.
Disposable gloves.
PVC knit wrist gloves.
PVC gauntlets.
Cut-resistance.
Heat-resistance gloves.
Anti-vibration gloves.
Welding gloves.
Kevlar nitrile cut-resistance gloves.
Waterproof work gloves.
Respirators:
Disposable dust masks.
Reusable respiratory masks.
FFP1-3 Masks.
Full-face masks.
Half-face masks.
Air-powered respirators.
Please note: The supplier can only make suggestions of the equipment which would protect against exposure, therefore you should conduct your risk assessments to ensure you select the correct controls to implement. Different chemicals circumstance will require different controls.
Confused by the many pieces of information provided in those safety data sheets? Join the International Association for Chemical Safety's completely free health and safety academy now and take the Safety Data Sheet Awareness Certification™.
This article was originally published by the team over at Sevron Ltd and has been shared here with full permissions.