155.88 is for emergency services,it broadcasts FD/EMS calls, as well as call suppliments that can not be broadcast over the air... example......
Radio: "Engine 113, respond to 123 xyz st, assist county police"
Pager : "0113,ENG113,123 xyz st,pers. inj.,asslt,taser deployed,PD OS"
46.12 is for TONE paging/station alerting....155.88 is for "conventional" text pagers,POCSAG