APA Controller voiced concern regarding local procedures and phraseology referencing run-up requirements that are confusing and not consistent with FAAO 7110.65.

Narrative

APA instituted a new procedure for aircraft to preform their run ups. This new procedure has increased radio congestion and confuses the pilots. The new procedure is that the ATIS SAYS THAT 'All departures advise when a run up is needed.' A good portion of the pilots are not following these directions and there for we have to ask each pilot if they are going to require a run up. The new run up area can only fit three small aircraft in it at a time and this is why we need to know if the pilots need a run up. The ATM has stated that if pilots are out of the run up area by even a little while doing their run ups; then it will lead to career problems for the controller. The run up area is marked by white paint which can not be seen from the Ground Control position; and therefore controllers can not guarantee that the pilots are in or out of it. The pilots do not go into this new run up box because it looks like another white painted box next to Runway 10 which pilots are NOT suppose to enter. This new procedure is not fixing the problem that we have had on ground for a while but rather it is adding to the problem. Recommendation; we need to use phraseology that is consistent with the FAAO 7110.65 and not try to reinvent the wheel. If we are not going to do that; then signs must be posted at the new run up area stating where pilots can and can not do there run ups. Also; the box needs to be painted differently so as not to be confused with the DO NOT DO RUN UPS area.