“…For instance, there is a wide literature to support water immersion (WI) colonoscopy wherever clinical familiarity allows this to take place—this technique also positively impacts procedural key performance indicators (painless insertion, decreasing sedation requirement, improve bowel cleanliness) as well as patient-centred outcomes (improved tolerance) and overall experience (advantageous for therapeutic applications) 108. The average volume of water used is estimated at 336 mL per gastroscopy (7.05 L for 21 oesophago gastro dudoenoscopy (OGDs)); 241 mL per sigmoidoscopy (5.3 L for 24 sigmoidoscopies) and 782 mL per colonoscopy (17.2 L for 22 colonoscopies) 107. If not all water of the 1000 mL container is used for the procedure itself, the remaining water could be employed in other steps in the use of endoscopes, for example, ‘bed-side’ cleaning.…”