(a) General. - (i) Also referred to as the "Clear Zone". This area, adjacent to the traveled lanes and including the paved shoulder or emergency parking lane, provides for an obstruction free recovery area for a driver to regain steering control should the vehicle leave the traveled lane.
- (ii) Highway appurtenances installed within this clear zone, except for barrier rail, are of the yielding or breakaway design.
- (iii) Obstructions located within the clear zone that can not be relocated must be protected with barrier rail if the rail provides the least hazard, and steep embankment slopes should be flattened.
- (iv) The actual clear zone width for a given segment of road is a function of the road's speed, horizontal curvature, and embankment slopes. It is not a standard fixed distance from the edge of the traveled lane as the often used term "30 ft. clear zone" would imply. However, the Department generally uses the area between the edge of the traveled lane and 40 feet parallel thereto for the installation of guardrail, delineators and traffic signs.
- (V) In any case, and on all types of roads, utility facilities should be located as close as possible to the outer limits of the highway right-of-way. Facilities that have to be located within the limits of the clear recovery area will be of a breakaway design.
- (vi) Actual clear zone required at a specific location and road shall be in accordance with the AASHTO Roadside Design Guide.
(b) High Speed Roads - Rural Areas. The Department generally uses the minimum distance of 30 feet from the edge of the traveled way as the transitioning point from a slope of no steeper than 6 to 1 to the steeper slopes required to reach natural ground and/or the drainage ditch.
Guardrail end anchorages, delineators, regulatory signs, and light standards are normally installed within the first 30 feet parallel to the traveled lane with large signs as far as 40 feet away.
The paved roadway, shoulder and the area up to 40 feet measured from the traveled lane shall be kept clear of above ground utility facilities due to the hazard they present, and clear of parallel buried facilities due to the restrictions they place on the Department for maintenance of slopes and shoulders, as well as construction, maintenance and repair of guardrail, delineators, signs, etc., unless the appropriate provisions of the AASHTO Highway Design publications require a more restrictive obstruction free area.
(c) Low Speed Rural Collectors and Rural Local Roads. On this type of road the minimum obstruction free area is 10 feet from the edge of traveled lane and/or 10 feet behind existing or proposed sidewalk and/or bicycle path.
(d) Urban Arterials, Collectors and Locals Streets. - (i) With Curb only - On this type of road the minimum obstruction free area should be 1.50 feet behind the curb.
- (ii) With Curb and Sidewalk - The obstruction free area shall extend to behind the existing or pro- posed sidewalk.