Digitisation Request form- Pop Up message to confirm CLA limits

We have done a lot of work with our academic colleagues to promote the Request Digitisation function when they need to request a scan. This has resulted in a lot using it but we are receving a lot of requests where someone is requesting a scan of 3/4 of a book's content (for example) which clearly exceeds CLA permissions. This has resulted in a lot of staff time having to triage and then contact the academic to reject the scan and explain why. A pop up message that appears when someone clicks on the Request Digitisation function to bring up the form would be helpful as a reminder of what the 10%/1 chapter rule is for Higher Education establishments, and may reduce the amount of requests we receive that greatly exceed what we can do, and save staff time.