National guidelines support infection control professionals, healthcare organizations and healthcare providers in the development, implementation and evaluation of infection prevention and control policies, procedures and programs to improve the quality and safety of health care and patient outcomes. [...] The purpose of the PHAC Guideline Infection Prevention and Control Guideline for Flexible Gastrointestinal Endoscopy and Flexible Bronchoscopy is to provide a framework within which those responsible for endoscopes in all settings, where endoscopy is performed, may develop policies and procedures to ensure that the critical elements and methods of cleaning, disinfection, and/or sterilization of th [...] These sections of the document are intended to provide the user with the knowledge and tools to ensure that the endoscopy working environment is safe for patients and staff, that staff are appropriately trained and competency assessment is ongoing, and that potential outbreaks of infection or reprocessing problems are identified and managed effectively and in a timely fashion. [...] Appendix I. The “PHAC Guideline Rating System” describes the system for ranking the strength of the evidence used to support the recommendations made in this Guideline. [...] However, the mucosal surface of the upper respiratory tract has a substantial load (~ 106 cfu/gm) of microorganisms(26) that can be carried down into the lower respiratory tract when the insertion tube of the bronchoscope is introduced into the lung through the mouth.