A top level general text on the subject with clear definitions and management principles:
www.jiscinfonet.ac.uk
Health & Safety Executive: "Sensible Risk Management"
www.hse.gov.uk/risk/
NHS Patient Safety Agency: NCAS & NPSA
www.ncas.npsa.nhs.uk/?i18n_lang=en
www.ncas.npsa.nhs.uk/toolkit
Root Cause Analysis - incident investigation
www.npsa.nhs.uk/patientsafety/
www.mindtools.com
NHS Employers - Healthy Workplace
www.nhsemployers.org/practice
COSHH & Risk Management
www.morethanbusiness.com
www.hse.gov.uk/coshh