Standards to Know Flashcards
Although crash involvement rates (crashes per 100,000 pop.) are highest for the five- to fifteen-year-old pedestrians, pedestrian fatality rates are highest for what age group?
70 years old and above
Under base conditions, what is generally considered to be freeway capacity?
2,250 to 2,400 passenger cars per hour per lane
What is the maximum superelevation rate that AASHTO recommends for locations where snow and ice conditions prevail?
8%
What are the colors most commonly used for regulatory signs?
white, black, and red
A “road safety audit” is?
a structured process by a team of qualified professionals focused solely on safety
Conversion of two-way streets to one-way flow can reduce what types of crashes?
pedestrian, left-turn, and rear-end
For a spot speed study, a sample size of how many vehicles is generally considered reliable under most circumstances?
100 vehicles per lane
Most commonly used form of traffic calming?
speed humps
What is the minimum vertical clearance for a sign installed above a sidewalk?
7 feet
Lettering requirement by MUTCD?
Lettering for names of places and streets on guide signs shall be a combo of lower-case letter with initial upper case letters
When timing pedestrian intervals for traffic control signals, what pedestrian walking speed should normally be used?
3.5 feet per second
When calculating stopping sight distance, what does the AASHTO use as a deceleration rate?
11.2 feet per sec per sec
Recommendation to use what value of perception-reaction time for calculating Stopping Sight Distance
2.5 seconds
By U.S. federal law, every urbanized area over what population size must have an ongoing transportation planning process?
50,000
Pedestrian Hybrid beacons should be installed where?
at each end of the marked crosswalk
Negligence means?
failure to do what an ordinary, reasonably prudent person would do under similar circumstances
MUTCD: warning and guides signs used for temporary traffic control in incident management situations may have a black legend with what color background?
fluorescent pink
MUTCD: traffic control signal Yellow Change intervals should be:
in the range of 3 to 6 seconds long
Speed limit within a speed zone should be posted within 5 mph of what?
the 85th percentile speed of free-flowing traffic
Traffic signal WALKING PERSON indication should be displayed for a minimum of:
7 seconds
A “short term stationary” temporary traffic control zone occupies a location for:
more than 1 hour within a single daylight period
A 16-hour traffic count, usually from 6 am-10 pm, normally accounts for what percentage of daily traffic on a roadway?
90-95%
When more than one countermeasure is being considered for implementation at a problem location, the CMF for the individual countermeasures are:
multiplied together
What is a traffic calming measure that widens the sidewalk for a short distance to reduce the crossing distance and allow peds and drivers to see each other when parked vehicles would otherwise block?
curb extension
