Measure the volume you actually lose
Record the beer removed from each line during a normal clean. Keep separate counts for lines with different lengths or products. If some beer is recovered safely for sale under your normal procedures, do not count it as waste. Keep a dated record across several cleans so one unusual session does not set the whole year's estimate.
For a quick illustration, multiply active lines by pints lost per line and by cleaning sessions per year. This is a planning formula, not a claim about a typical venue. Connected keg count helps describe the cellar but is not another multiplier in this volume calculation.
Value stock and sales separately
Multiply potentially avoidable pints by the beer's cost per pint to estimate stock cost avoided. You may also look at those pints at selling price as a possible revenue scenario, but that assumes demand, availability and successful sale. Adding both figures together would count the same beer twice.
A longer cleaning interval can change this volume only where the system supplier approves the venue's process and quality requirements. Do not extend an ordinary cleaning schedule from a financial estimate alone.
Use the result as a decision input
Compare the measured loss with staff time, chemicals and any quoted system cost. The savings calculator keeps those components visible. Ask the supplier to confirm the proposed interval and any initial cleaning requirements before treating the comparison as a forecast.
Use your venue's figures
Compare cleaning waste, staff time and supplies. Add DING's written costs before reading a net estimate.
Sources and review
Venue-specific method and any DING interval require supplier confirmation.