Delaware Administrative Code
Title 2 - Transportation
2000 - Department of Transportation
2400 - Division of Transportation Solutions
2402 - Manual on Uniform Traffic Control Devices (MUTCD)
Part 6 - Temporary Traffic Control
Chapter 6C - TEMPORARY TRAFFIC CONTROL ELEMENTS
Section 6C.06 - Activity Area
Current through Register Vol. 28, No. 3, September 1, 2024
Support:
01 The activity area is the section of the highway where the work activity takes place. It is comprised of the work space, the traffic space, and the buffer space.
02 The work space is that portion of the highway closed to road users and set aside for workers, equipment, and material, and a shadow vehicle if one is used upstream. Work spaces are usually delineated for road users by channelizing devices or, to exclude vehicles and pedestrians, by temporary barriers.
Option:
03 The work space may be stationary or may move as work progresses.
Guidance:
04 Since there might be several work spaces (some even separated by several miles) within the project limits, each work space should be adequately signed to inform road users and reduce confusion.
Support:
05 The traffic space is the portion of the highway in which road users are routed through the activity area.
06 The buffer space is a lateral and/or longitudinal area that separates road user flow from the work space or an unsafe area, and might provide some recovery space for an errant vehicle.
Guidance:
07 Neither work activity nor storage of equipment, vehicles, or material should occur within a buffer space.
Option:
08 Buffer spaces may be positioned either longitudinally or laterally with respect to the direction of road user flow. The activity area may contain one or more lateral or longitudinal buffer spaces.
09 A longitudinal buffer space may be placed in advance of a work space.
10 The longitudinal buffer space may also be used to separate opposing road user flows that use portions of the same traffic lane, as shown in Figure 6C-2.
11 If a longitudinal buffer space is used, the values shown in Table 6C-2 may be used to determine the length of the longitudinal buffer space.
Support:
12 Typically, the buffer space is formed as a traffic island and defined by channelizing devices.
| Table 6C-2. Stopping Sight Distance as a Function of Speed | ||||
| Speed* | Distance | |||
| 20 mph | 115 feet | |||
| 25 mph | 155 feet | |||
| 30 mph | 200 feet | |||
| 35 mph | 250 feet | |||
| 40 mph | 305 feet | |||
| 45 mph | 360 feet | |||
| 50 mph | 425 feet | |||
| 55 mph | 495 feet | |||
| 60 mph | 570 feet | |||
| 65 mph | 645 feet | |||
| 70 mph | 730 feet | |||
| 75 mph | 820 feet | |||
| * | Posted speed, off-peak 85th-percentile speed prior to work starting, or the anticipated operating speed | |||
13 When a shadow vehicle, arrow board, or changeable message sign is placed in a closed lane in advance of a work space, only the area upstream of the vehicle, arrow board, or changeable message sign constitutes the buffer space.
Option:
14 The lateral buffer space may be used to separate the traffic space from the work space, as shown in Figures 6C-1 and 6C-2, or such areas as excavations or pavement-edge drop-offs. A lateral buffer space also may be used between two travel lanes, especially those carrying opposing flows.
Guidance:
15 (DE Revision) The width of a lateral buffer space should be determined by engineering judgment. On interstates, freeways, or expressways, a lateral buffer space of one travel lane should be used, except where temporary traffic barrier is used to separate the work area from the traveled way, or if other conditions prevent the use of a lateral buffer space.
Option:
16 When work occurs on a high-volume, highly congested facility, a vehicle storage or staging space may be provided for incident response and emergency vehicles (for example, tow trucks and fire apparatus) so that these vehicles can respond quickly to road user incidents.
