Can someone provide a risk assessment for interceptor cleaning that I can double check against my own. Many Thanks in advance

Not normally a fan of outsourcing but if you are able, get a specialist contractor in to do this work. By it's very nature it can be quite specialist and dependant on the size of interceptor quite hazardous. Then there is what to do with the waste that comes out. A competent contractor will provide full risk assessments, method statements and any relevant training information for their people, and they will deal appropriately with the waste and provide waste transfer documentation. You should be able to assess their documentation and work practices to ensure they are fit for purpose before work starts.