What is a Nanomaterial/Nanotechnology?
Refer to HSE Guidance on Nanotechnology.
A Nanomaterial (European Commission Recommendation 2011/696/EU) is defined as a natural, incidental or manufactured material containing particles, in an unbound state or as an aggregate or agglomerate and where, for 50% or more of the particles in the number size distribution, one or more external dimensions is in the size range 1 nm - 100 nm. In specific cases and where warranted by concerns for the environment, health, safety or competitiveness the number size distribution threshold of 50 % may be replaced by a threshold between 1 and 50%. By derogation, fullerenes, graphene flakes and single wall carbon nanotubes with one or more external dimensions below 1 nm should be considered as nanomaterials.
High Aspect Ratio Nanomaterials (HARNs) are fibrous nanomaterials where the length is many times the width such as certain types of carbon nanotubes, nanorods or nanowires. Research shows there is sufficient evidence to suggest that HARNs which have the same characteristics (diameter, length and biopersistance) as pathogenic fibres, such as asbestos, are likely to have similar pathology. Therefore, more robust control measures need to be considered when assessing the risk from these types of nanomaterials.
Risks with using Nanomaterials
The potential risk to health and the environment to Nanomaterials is currently relatively unknown and research is being undertaken. Therefore, there is a need to take specific considerations into account during their risk assessment. Exposure to some particulate nanomaterials can occur by ingestion, skin penetration or inhalation, with the resultant adverse effects depending upon the size, dose and toxicity of the nanoparticle. Toxicity investigations indicate that the effects appear to be related to the total surface area of the particles. The exposure potential will be directly related to the structure and form of the nanomaterial. The exposure risk to particles encapsulated in a matrix or strongly adhered to a substrate will be lower than that from ‘free’ aerosolised, particulate nanomaterials.
Process for using Nanomaterials Safely
This process does not cover the incidental release of nanomaterials such as those from diesel exhaust and welding fumes. It also does not include other properties of nanomaterials in detail as defined under the COSHH Regulations 2002. These are covered by the Hazardous Substances Standard that should be implemented in conjunction with the requirements of this document.
There are specific requirements that need to be met before work with Nanomaterials can be started at the University. These are:
Notify UHSE of proposed new nanomaterial work and supply a copy of the risk assessment for review prior to work commencing. Refer to HSE Guidance.
Ensure the risk assessment justifies the use of nanomaterials (where cannot be eliminated) and takes into account their specific properties. Refer to UK NanoSafety Group Guidance.
- minimise amount of material handled/stored (includes bulk material purchased)
- minimise potential for airborne release
- minimise number of persons exposed
- minimise exposure time
- other hazardous properties i.e. toxic, carcinogen, mutagen
- Identification of appropriate control measures; LEV and PPE
Implement a sensible precautionary approach to risk management of nanomaterials due to the uncertain or not clearly defined toxicology particularly for exposure via inhalation, ingestion, or absorption.
Apply stricter risk management of control for HARNs (see HSE Guidance)
- Robust justification for use
- Minimise likelihood of becoming airborne (keep wet/damp)
- Fully enclose process when aerosol intentionally generated i.e. use of glovebox
- Provide RPE for emergencies (minimum assigned protection factor APF40)
Ensure users are trained in the particular hazards and control measures required when working with nanomaterials.
Identify appropriate clean-up and waste disposal procedures
- wet wiping; DO NOT brush or use compressed air
- only use a dedicated HEPA filtered vacuum
- waste should be considered hazardous (unless it can be demonstrated otherwise)
This guidance is supported by a more detailed Standard which is available from UHSE.