Reflective Street Signs Required,
Increased Letter Size Recommended
Recent changes to the Manual on Uniform Traffic Control Devices (MUTCD) affect municipal street name signs. The compliance date is January 9, 2012 to allow state and local agencies to make the required and recommended changes.
The first change is to require retroreflective street name signs. The MUTCD had recommended reflectorized or illuminated signs. In other words, retroreflectivity for street signs has changed from an advisory to a mandatory condition.
The second change is a recommendation for an increase in letter size. On local roads with speed limits greater than 25 mph, signs should have 6 inch uppercase letters, 4 1/2 inch lowercase letters, and 3 inch letters for street abbreviations or city sections (e.g., Avenue, Road, NW.). For local roads with speed limits 25 mph or less, the existing MUTCD language is modified to provide an option for the continued use of a minimum 4 inch uppercase letter size with 2 inch lowercase letters for street abbreviations or city sections.
The Federal Highway Administration recognized that the change from 4 to 6 inch letter sizes would impose some additional costs on state and local jurisdictions. It therefore established January 9, 2012 as the compliance date for installing street name signs with these changes.
This long period gives New Hampshire municipalities time to decide how and when they will comply with these changes. One factor to consider is that reflectorized signs increase motorist safety. In addition, the larger lettered signs are more convenient for motorists and passengers. Several towns are already installing 6-inch lettered signs on major roads.
Cost, on the other hand, is a negative factor. A 6-inch lettered sign costs about twice that of 4-inch. Post and hardware costs also increase significantly. The added cost is due to the size of the signs. Signs with 4-inch letters are 6 inches high; signs with 6-inch letters are 9 inches high. Six-inch lettered signs are also longer, and require heavier posts and hardware.
Source:
http://adata.org/fr97/010997a.htm