Some practices still use in house sterilisation. This is still possible for practices to do but they must follow quite rigid guidelines if they are to continue to do so. The Health and Social Care Act 2008 - code of practice on the prevention and control of infections and related guidance does now applies to practices since CQC registration came into force though. In terms of decontamination it points to several documents including HTM 01-012 and 2007 Clarification and Policy Summary Decontamination of Re-useable Medical Devices in the Primary, Secondary and Tertiary Care Sectors (NHS and Independent providers). You certainly need to have tracking and traceability of instruments and quite regular checking and cleaning routines detailed in the documents referenced.
Most practices undertook a cost benefit analysis several years ago and found little difference in cost, and many freed up staff time by moving to single re-useable instruments. At the LMC we certainly share frustration about the lack of evidence around infection spread in primary care, and the waste with single use instruments.
It is worth taking a look at Appendix D of The Health and Social Care Act 2008 , where there are examples of interpretation for Primary Care, and at Part B: Additional management guidance and common elements; Part C: Sterilizers; and Part D: Washer disinfectors and ultrasonic cleaners in the DoH HTM 01-01