1. CTC-340 Signals - Basics

2. Elements of Signal design Safe & effective phase plan Determine vehicular signal needs –Y, vc, L, C –Effective green allocation Ped needs

3. General Considerations in Signal Phasing Minimize accident risks by competing movements Increase LT sat flow rates Must be in accordance with MUTCD Must be consistent with geometrics, volumes, speeds, peds

4. Lt Turns Figure 21.1 gives guidance Pg 490-491

5. Phase rings Fig 21.2 shows common arrows Fig 21.3 shows a simple ring Fig 21.4 ring with LT phase Fig 21.5 Lead/lag green Fig 21.6 lead/lag with leading green Fig 21.7 8 phase ring Fig 21.8 Ped phase

6. Right Turns Protected RT –hi ped rates –In conjunction w/protected LT RTOR –Used unless Inadequate sight distance High speed conflicting veh Hi ped flows

7. Change & Clearance Interval Change = yellow time –y= t + (1.47S 85 )/(2a+(64.4*0.01G)) Clearance = all red –ar = (w+L)/1.47S 15 –ar = (P+L)/1.47S 15 –P = dist from stop line to farthest conflicting traffic lane