In this section, Part 4 of this series, we'll start by looking at more precise calculations for determining the area needed for a sign or banner.
Personally, I am not a big fan of algebra, but sometimes the easiest way to calculate what the Area of a sign (A[sign]) is by using one, especially if someone else has already done the work to come up with it, which, in our case, the USSC has already done for us.
How to Measure the Area of Signs or Banners
The only part of the equation that is left out is the negative space calculation, which is fixed at a 40/60 ratio with the copy area, or Copy Area x 1.5. Note that number rounding - which I do frequently - will yield a slight variance in copy area/negative space. As this is an inexact science to a degree, this rounding will likely have little effect on readability of your signs or banners. This is essentially the same formula used in Part 3, but it's simplified from the 10 step equation to this -
A(sign) = 3n/80 [(VRT)x(MPH)/LI]
Fixed Value:
40/60 ratio of copy area to negative space
Variable Values:
N = number of letters
VRT = Viewer Reaction Time
MPH = Miles Per Hour b
LI = Legibility Index
Doing the Calculation
How do I use this equation in the real world? First, take the number of letters (N) and multiply it times 3, then divide that by 80. So, we'd take 3 x 60 /80 =.75. Set that number aside.
Next, we want to multiply our VRT - 10 seconds - times the MPH - 40mph = 400, divide it by the LI - 30 = 13.33 - and square it = 178 rounded up. Now multiply 178 x.75 and your sign's square footage would be 133.5. Much simpler than the longhand equation, methinks!
An even simpler equation, but with more fixed values, is this algebraic equation -
A(sign) = [(VRT)x(MPH)] x [(VRT)x(MPH)] / 800
Fixed Values:
Number of Letters - 30
LI (Legibility Index) - 30
Copy Area/Neg. Space - 60/40
Variable Values:
VRT (Viewer Reaction Time)
MPH (miles per hour)
This equation works quite simply as you multiply view reaction time - 10 seconds - times the miles per hour - 50mph = 500 and then square it = 250,000 and divide it by 800 = 312. This is the area of your sign.
Now you'd need to know that you'll have 30 - 30 in. letters, which is a fixed value above, and that these letters will fit into this area. You may need to vary the sign area if the words require it, like we did on the Grand Opening banner in the last section.
In the final installment of this series, Part 5, I'll discuss parallel signs. These present their own challenge, so I will deal with them completely separately from the previously discussed signage.
ABOUT THE AUTHOR
Barry K. Brown has been in the Sign, Banner, Decal and Display Business for over 20 years. It isn't what he thought he'd do with his life, but he says he knows too much now to do anything else!
He has been marketing these products online since 1998, and the company he was general manager of in 1998 was the first sign company to be listed on Yahoo!
He invites you to visit his web page on customized outdoor signs online at www.visigraph.com/signs-letters/ for wholesale custom signage.