1. Training
2. Center
3. High/Low Center Sectorizations

High/Low splits allow for another method of sectorization which can balance the workload of en route separation and remote field operations.

Low Sectors:

• Control ZSE from the surface, including all unstaffed local and TRACON positions, to FL230.
• Assign climbing aircraft filed FL240 and above FL230 as the intermediate altitude.
• Descend aircraft coming from the High sector to at/below FL230

High Sectors:

• Control ZSE from FL240 upward.
• Assign aircraft landing ZSE or southwest ZVR pilot's discretion FL240
• Climb aircraft coming from the Low sector to at/above FL240

2-Way Split:
Seattle Low sector shall log on with the callsign SEA_L_CTR. Low sector shall Use a frequency of 124.20. Low sector shall control ZSE at/below FL230

Seattle High sector shall log on with the callsign SEA_H_CTR. High sector shall use a frequency of 135.15. High sector shall control ZSE at/above FL240.

4-Way Split:
Seattle Low North sector shall log on with the callsign SEA_LN_CTR. Low North shall use a frequency of 123.95. Low North shall control the combined A and C sectors at/below FL230.

Seattle Low South sector shall log on with the callsign SEA_LS_CTR. Low South shall use a frequency of 127.60. Low South shall control the combined B and D sectors at/below FL230.

Seattle High North sector shall log on with the callsign SEA_HN_CTR. High North shall use a frequency of 128.45. High North shall control the combined A and C sectors at/above FL240.

Seattle High South sector shall log on with the callsign SEA_HS_CTR. High South shall use a frequency of 135.15. High North shall control the combined B and D sectors at/above FL240.


Individual Sub-Sectors to use for work balancing:
Seattle Low A sector shall log on with the callsign SEA_LA_CTR. Low A shall use a frequency of 125.10. Low A shall control the A sector at/below FL230.

Seattle Low B sector shall log on with the callsign SEA_LB_CTR. Low B shall use a frequency of 125.80. Low B shall control the B sector at/below FL230.

Seattle Low C sector shall log on with the callsign SEA_LC_CTR. Low C shall use a frequency of 126.10. Low C shall control the C sector at/below FL230.

Seattle Low D sector shall log on with the callsign SEA_LD_CTR. Low D shall use a frequency of 127.60. Low D shall control the D sector at/below FL230.

Seattle High A sector shall log on with the callsign SEA_HA_CTR. High A shall use a frequency of 126.60. High A shall control the A sector at/above FL240.

Seattle High B sector shall log on with the callsign SEA_HB_CTR. High B shall use a frequency of 134.65. High B shall control the B sector at/above FL240.

Seattle High C sector shall log on with the callsign SEA_HC_CTR. High C shall use a frequency of 128.45. High C shall control the C sector at/above FL240.

Seattle High D sector shall log on with the callsign SEA_HD_CTR. High D shall use a frequency of 135.15. High D shall control the D sector at/above FL240.