But counting crashes and fatalities obscures an even more treacherous reality.

The City of Philadelphia has a number of safety initiatives through their Vision Zero program -- named Vision Zero as the goal is to eliminate traffic fatalities.

What is Daylighting? Streetfilms has a great introduction video, and SFMTA has a useful article and this picture below.

Before we answer this question, let's look at the regulations. The Pennsylvania Vehicle Code requires that the no-parking zone stretch about 30 feet back from the crosswalk of a stop-signed controlled intersection. Let's see if a 10 degree angle of vision range for a driver would capture a waiting pedestrian.

We'll solve for the angle theta, which represents the angle of vision a driver 30 feet away from the crosswalk would HAVE TO HAVE to see a waiting pedestrian. If theta is greater than 10 degrees, then we know that the PA Vehicle Code regulation does not ensure safety, and that parking should only be allowed further than 30 feet away from the crosswalk.

**Steps to solve: **

1) Measure, ideally with a flexible table measure, the base and height of the triangle

in our example, a typical South Philly one-way street with parking on both sides, the base is 12 feet and the height is 30 feet

2)**Find the hypotenuse of the triangle, h, using the Pythagorean Theorem! **

base^2 + height ^2 = hypotenuse ^ 2

In our example, the hypotenuse^2 = 12^2+30^2 = 144; 144^.5 = 32.3 feet

3) Use geometry to find Theta

sin Theta = opposite side/hypotenuse

In our example, sin Theta = (12 feet/32.3 feet) = 20.81 degrees

In our example, a driver in a car 30 feet away from the intersection would need to have a ranger of peripheral vision that is 20.81 degrees ON EITHER SIDE (41.68 degrees total) to see a waiting pedestrian! Since a driver only has about 10 degrees of vision on either side, a pedestrian waiting at this intersection would be very hard to see.

PA Vehicle Code needs to be revisited for safety. More than that, many intersections around Philly violate the vehicle code, and have a no-parking zone between the crosswalk and the first parked car that is much shorter than 30 feet.

Our goals are to: 1) promote understanding of how daylighting can make crossing intersections safer for pedestrians 2) measure how intersections in Philly are doing in terms of providing adequate no-parking zones and put these on an interactive map and 3) encourage the city to daylight parking throughout the city to improve the visibility of pedestrians.

**What can you do? **

We are starting the Philadelphia Daylighting Project to highlight how visible pedestrians are at different stop-sign controlled intersections around Philadelphia. We are asking everyone to measure distances at intersections close by to you around Philadelphia. We will calculate the sight distance required and then map the results.

Please use the google form to carefully record the intersection, the exact side of the street, the distance of the street crossing from curb to curb, and the distance of the no parking zone (the distance from the middle of the crosswalk to the start of the parking zone).

]]>1) Measure, ideally with a flexible table measure, the base and height of the triangle

in our example, a typical South Philly one-way street with parking on both sides, the base is 12 feet and the height is 30 feet

2)

base^2 + height ^2 = hypotenuse ^ 2

In our example, the hypotenuse^2 = 12^2+30^2 = 144; 144^.5 = 32.3 feet

3) Use geometry to find Theta

sin Theta = opposite side/hypotenuse

In our example, sin Theta = (12 feet/32.3 feet) = 20.81 degrees

In our example, a driver in a car 30 feet away from the intersection would need to have a ranger of peripheral vision that is 20.81 degrees ON EITHER SIDE (41.68 degrees total) to see a waiting pedestrian! Since a driver only has about 10 degrees of vision on either side, a pedestrian waiting at this intersection would be very hard to see.

PA Vehicle Code needs to be revisited for safety. More than that, many intersections around Philly violate the vehicle code, and have a no-parking zone between the crosswalk and the first parked car that is much shorter than 30 feet.

Our goals are to: 1) promote understanding of how daylighting can make crossing intersections safer for pedestrians 2) measure how intersections in Philly are doing in terms of providing adequate no-parking zones and put these on an interactive map and 3) encourage the city to daylight parking throughout the city to improve the visibility of pedestrians.

We are starting the Philadelphia Daylighting Project to highlight how visible pedestrians are at different stop-sign controlled intersections around Philadelphia. We are asking everyone to measure distances at intersections close by to you around Philadelphia. We will calculate the sight distance required and then map the results.

Please use the google form to carefully record the intersection, the exact side of the street, the distance of the street crossing from curb to curb, and the distance of the no parking zone (the distance from the middle of the crosswalk to the start of the parking zone).