To: GURA Board,

 

FM: Preston

 

 

     Re: Proposed Pedestrian Signs on Washington

 

 

First off, I like the idea of the electronic sign board that can be changed to get drivers’ attention on Washington Avenue coming into the downtown.

 

When I re-reviewed the TrueImage information on the website (www.adsled.com ), I was struck by the fact that all of the “solutions” by the firm and what seems to be all of the pictures of their sample signs and even the recently sent Denver example on the Auraria Campus are 5 inch letters or greater.  

 

Five inch lettered signs are shown on the home page at adsled.com, yet one has to hunt to find the 4 inch letter signs.  Further, the fact that the local distributor can’t find a 4 inch sign in metro Denver is also troubling. The info Dan sent us for the Washington Avenue signs call for 4” letters. I do not know which size would work best given our requirements, but this raises the obvious question of what are the advantages and disadvantages of 4 inch vs.5 inch letters on TruImage electronic signs. This led me to do further research.

 

 

The information on Model 221-4 (the model in the Proposal) and Model 221-5 are shown on the attachment. The “4” and the “5” refer to the height of the letters. The first “2” in the model number refers to two lines of text. The next to digits “21” refer to the minimum number of alpha characters per line (21). The number of characters per line (21 – 24) is dependent on the different width of the letters in our alphabet, for example, “m” takes up more width requirement than an “i”.  An “s” in front the model number refers to a “single sided” sign. The proposal calls for a single sided sign, 2 line, 4 inch letters.

 

From the technical descriptions both models use the same “pixel matrix.” Both models have the same wireless electronics .The actual length of the two signs vary by only 5 inches (6’-11” and 7’-4”).  Although counter-intuitive, the height of the 5 inch letter model is shorter than the 4 inch model (model 221-4 = 16 inches and Model 221-5 = 11 inches). Those are the dimensions on the website shows. There are different mounting options, but there are no comparisons of the mounting dimensions for the two models. Both signs are operational down to 5 degrees Fahrenheit so on extremely cold days neither sign would be expected to work.   

 

  

Travel Distance and Time

 

The two lines with 4 inch letters can be seen at 200 feet (per email sent by Paul Kuhn to Dan Hartman) and 5 inch letters can be seen from 700 feet per the adsled.com  website.

 

Four Inch Letters

From the traffic data sent to us from Dan, 50 percent of the cars going south bound on Washington and 8^th Avenue travel at 29 mph or faster. Using 32 mph as a reasonable speed for a vehicle at 8^th, Street, the vehicle covers 47.04 feet per second (1 mph = 1.47 ft/sec) or travels in 200 feet in 4.25 seconds.

 

This means the driver has slightly over 4 seconds to read two lines of 4 inch text traveling at 32 miles per hour. This calculation also assumes the driver is not interrupted by any other visual conditions. At 35 mph, the comparable view time is 3.9 seconds and at 40 mph the view time is 3.4 seconds. The calculations here are for speeding vehicles as the purpose of both proposed signs is to slow down the faster drivers.     

 

Five Inch Letters

For a vehicle traveling at 32 mph with a 5 inch sign, the 700 feet distance is traveled at 14.9 seconds thus the view time is just under 15 seconds. At 35 mph, the view time is 13.6 seconds and at 40 mph the view time is 11.9 seconds. This data clearly shows why the large letters are used more frequently for these types of signs.

 

 

Comparison Signs in Golden

 

For comparison purposes, the letters on the City’s directional blue signs are 2 ½ inches with caps at 3 ¾ inches. The electronic Golden High School sign has letters at 24 inches in height. The electronic speed measuring sign at 19^th Street has letters 18 inches high. The actual “Speed Limit” sign at the same location has wide, bold 4 inch letters.

 

Having dealt with some signage issues in a prior life, I know that visibility is based on the letter size, letter color, type of font, background color, ambient light as well as the other factors that we often do not think about. Some signs work and others do not. A sign that works for pedestrians does not work for vehicle drivers and a sign designed for a quiet residential street is not necessarily readable on a busy commercial street. It is for this reason that I asked for an example in Denver of the proposed 4 inch sign.

 

 

View Angles

 

The viewing angle of 125 degrees noted on the Proposal indicates the horizontal “width” of view from which the sign can be read. In our case, depending on the angle of the sign relative to on-coming traffic, it is very possible a person walking on the sidewalk probably could read the text very clearly. 

 

The other angle which is not discussed on the website is the “vertical” pitch. It is not clear from the website or the Proposal if “continuous angle brackets” refers to this vertical adjustment. Most of the signs shown on the website are on flat streets. Coming down Washington from Col 58 bridge, the street is at very steep angle. It will be the same with the new bridge. As most single sided signs are mounted on sides of buildings, we need to make sure that if the single sided sign is mounted on a flat brick surface, (or other flat surface) that it can be adjustable for vertical pitch to optimize the diver’s view of the text on Washington Avenue.

 

 

Recommendations

 

Based on the above information and data, the proposed 4 inch signs and the existing speed on commercial Washington Avenue, the 3 to 4 seconds of sign exposure does not seem adequate to do what we want done.

 

So far have there is no way of testing or actually seeing a 4 inch sign in use on a busy commercial street. As these signs are custom made based on orders received, there does not seem to be a way of looking at one “off the shelf” or bring it to the site. Further, the four inch signs are primarily for text-based applications with ability to do some basic graphics and animations.     

 

A 5 inch letter would work better based on driver viewing time and the fact that most signs in commercial areas are 5 inches or greater. The 5 inch sign has the added advantage of being able to support full graphics with animation if we get creative in the future.  

 

I would propose that GURA board be willing to pay the difference between the purchase and installation of price a 5 inch sign versus a 4 inch sign when we get to that point in the decision process. As this is an investment some public dollars to accomplish our intent, we should work towards the best option in this signage to accomplish the goal of making downtown Golden pedestrian friendly.