Police services provided by the Houston Police Department.  
Fire/Rescue/EMS services provided by the Houston Fire Department.

For airport operations, see Harris County Regional Radio System trunked radio system.

Atlantic Southeast Airlines ("Candler") doing business as Delta Connection.
Comair doing business as Delta Connection.

Air Traffic Control:
Houston Terminal Radar Approach Control (TRACON)
124.6    S [ CSQ ] Automatic Terminal Information Service (ATIS)
125.45   S [ CSQ ] Clearance Delivery
121.9    S [ CSQ ] Ground
118.7    S [ CSQ ] Tower

Aviation - Airlines:
130.975  S [ CSQ ] AirTran ("Citrus") -- license cancelled 7/17/2008 ??
131.95   S [ CSQ ] American / American Eagle ("Eagle Flight")
129.8    S [ CSQ ] Continental - Maintenance 
129.175  S [ CSQ ] Delta / Delta Connection (includes Champion)
131.7    S [ CSQ ] Southwest - Dispatch
131.225  S [ CSQ ] Southwest - Operations/Maintenance

Aviation - Fixed Base Operators:
130.75   S [ CSQ ] Atlantic Aviation
131.975  S [ CSQ ] Enterprise Air Center
122.95   S [ CSQ ] Fletcher Aviation
131.9    S [ CSQ ] Million Air
130.575  S [ CSQ ] Raytheon Aircraft Services
129.35   S [ CSQ ] Wilson Air Center

Airline Ground Operations:
460.775  R [114.8] American (includes ATA, JetBlue and Sun Country)
460.825  R [103.5] Delta
463.6125 R [d 065] Southwest - Aircraft Maintenance
461.2125 R [d 732] Southwest - Customer Relations
462.5    R [d 156] Southwest - Gate Agents
463.9125 R [d 065] Southwest - Provisioning
464.625  R [d 371] Southwest - Ramp (Baggage/Cargo/Fueling)
461.5125 R [d 664] Southwest
464.6125 R [d 156] Southwest

Federal:
172.9    R [n 001] Transportation Security Administration (TSA)
169.3    I [n 001] Transportation Security Administration (TSA)

Miscellaneous Airport Services:
464.55   M [127.3] Continental? Aircraft Maintenance
462.025  R [d 532] International RAM Associates
452.7375 R [d 532] International RAM Associates (Wheelchairs) (obsolete?)
467.9    S [d 315] SkyCaps (Wheelchairs)

Parking Shuttles:
469.925  S [d 245] Pre-Flight Airport Parking
461.3375 S [d 664] Unidentified

Rental Cars:
452.3125 R [107.2] Hertz

Unidentified:
453.025  S [162.2] ?
463.8375 S [250.3] ?
466.2625 M [d 343] ? going to baggage

Related Links:
AirNav
FAA Airport Diagram