1. AASHTO SCOTE Annual Meeting – June 14-17, 2009 NCUTCD Summer Meeting – June 18-20, 2009 Manchester, New Hampshire

2. Section 2E.21 of the MUTCD indicates: Changeable message signs should be capital letters and have a desirable letter size of 450 mm (18 in) or a minimum letter size of 265 mm (10.6 in). Section 7.2 of the Changeable Message Sign Operation and Messaging Handbook, August 2004 (FHWA-OP-03-070) indicates: Character heights on CMSs used on freeways and other high- speed highways should not be less than 18 inches National Electrical Manufacturers Association (NEMA) TS4-2005 standard defines character height as: “the vertical pitch times the number of pixels in the column of pixels”, or 7 x (Vertical Pitch)

3. 18” H C = Character Height P = Pitch (distance between LED’s) Ø LED = LED Pixel Diameter 18” Character Example Ø LED = 1.25” P = 2.57” H C = 7 X 2.57” = 18” or H C = 6 X 2.57” + 1.25” = 16.7” 18” 16.7 ” P=2.75” Ø LED =1.5” P=2.57” Pixel “Bloom” Character Height using Physical Measurement H C = 6 X P + Ø LED Character Height using NEMA TS4 Definition H C = 7 X P 18” Character Example Ø LED = 1.5” P = 2.75” H C = 6 X 2.75” + 1.5” = 18” Ø LED =1.25”

4. Vendor Using NEMA TS4 Definition Sign Height = 93” Vendor Using “Physical” Measurement Sign Height = 101”

5. Florida Department of Transportation submitted NEMA TS-4 request for interpretation on November 10, 2008 NEMA Technical DMS Committee responded on March 11, 2009: “The NEMA DMS Technical Committee does not see this request for interpretation as a reason to revise the TS_4 standard, but instead recommends that the standard be followed as written and that agencies require their vendors to provide all the necessary documentation and test results to prove their conformance to the standard. “

6. Section 4J.03 of the MUTCD indicates: Nominal minimum height and width of each DOWNWARD GREEN ARROW, YELLOW X, and RED X signal face shall be 450 mm (18 in) for typical applications. The WHITE TWO-WAY LEFT-TURN ARROW and WHITE ONE WAY LEFT-TURN ARROW signal faces shall have a nominal minimum height and width of 750 mm (30 in). The color of lane-use control signal indications shall be clearly visible for 700 m (2,300 ft) at all times under normal atmospheric conditions, unless otherwise physically obstructed. How is the lane-use control signal face measured?

7. Vendor with 18” High Symbol Vendor with 13” High Symbol Vendor with 17” High Symbol

8. Vendor with 18” High Symbol Vendor with 13” High Symbol Vendor with 17” High Symbol

9. Section 4J.02 of the MUTCD indicates: The meanings of lane-use control signal indications are as follows: ……. E. A steady RED X signal indication shall mean that a road user is not permitted to use the lane over which the signal indication is located and that this signal indication shall modify accordingly the meaning of all other traffic controls present. Section 4J.04 of the MUTCD indicates: A moving condition in one direction shall be terminated either by the immediate display of a RED X signal indication or by a YELLOW X signal indication followed by a RED X signal indication. Is a Flashing Red X operation allowed if no Yellow X indication exists?

10. Answers?