Techniques to reduce incidents of sign vandalism include steps that address the reasons
for vandalism, enable the prosecution of offenders, ease maintenance, and make it more
difficult to perform the vandalism. Consider the following to reduce vandalism:
• The theft and damage to many street name signs is due to the similarity to someone’s name. Vandalism to signs can often be reduced by adding St., Ave., or Blvd. to the sign.
• Use only standard signs. Signs that have an unusual message experience a higher vandalism rate.
• Use sign blank materials that are less susceptible to specific types of vandalism. Thicker-gage aluminum sign blanks can be used in areas that are subject to damage by bending. Plywood sign blanks are less susceptible to gunshots. Aluminum signs, when struck by gunshot, are indented over a /f-in-diameter (12.5-mm) circle per bullet hole, resulting in severe chipping and loss of reflectivity and legibility. Plywood signs remain legible even with numerous bullet holes. Plywood signs are also a less attractive target than aluminum signs, since they provide less noise and movement when used for target practice.
• Place an agency identification sticker on the back of each sign. This sticker should have a unique number for each sign, the agency name, whom to contact if the sign is found, and a warning about the legal consequences of stealing or damaging the sign. The identification sticker enables law enforcement officials to prosecute individuals stealing or vandalizing the sign. The date of installation can also be placed on the sticker for maintenance information.
• Apply protective coatings to the sign face to ease the removal of foreign substances. Clear coatings, such as product number 711 or 731 from the 3M Company, can be applied by spraying, roll coating, or hand brushing. Transparent overlay films such as Scotchlite brand graphic overlay (GOF™) from the 3M Company are also available. The clear coatings and overlays allow the removal of crayon, paint, lipstick, and other contaminants with the use of strong solvents that would normally harm uncoated sign face material.
• Support twisting or removal can be reduced by installing approved supports of a heavier gauge and using anchor plates. Driven sign supports, as opposed to those installed by drilling and backfilling, are less susceptible to twisting.
• Use commercially available antitheft fasteners that make it difficult for vandals to remove signs. These fasteners include Tufnet, Teenut, aluminum fluted nuts, blind aluminum rivets, and Vandalgard nuts as illustrated in Figs. 7.54 through 7.56.
NEOPRENE
OR
NYLON WASHER
PLYWOOD SIGN
TUFNUTS’
t JUNCTION
NYLON WASHER
TYPICAL INSTALLATION PROCEDURE
STEP 1: INSTALL FIRST TUFNUT (N0.1) FINGER TIGHT AS SHOWN.
STEP 2: INSTALL SECOND TUFNUT (NO. 2) FINGER TIGHT AS SHOWN.
STEP 3: INSTALL WRENCH AT JUNCTION TO TIGHTEN (OR LOOSEN) AS NECESSARY
STEP 4: REMOVE TUFNUT NO. 2; THEN INSTALLATION IS COMPLETE.
SINGLE TUFNUT IS DIFFICULT TO REMOVE BECAUSE OF ITS SHAPE
ALWAYS USE FOUR TUFNUTS FOR EACH SIGN INSTALLATION.
TYPICAL TUFNUT (FOR 10 DIA CARRIAGE BOLT)
TYPICAL TUFNUT
(FOR 10 DIA CARRIAGE BOLT)
FIGURE 7.55 Vandalgard sign fastener.
PLACE NYLON OR FIBER WASHER
BETWEEN SIGN FACE AND PALLET
WOOD POST SUPPORT (DIMENSION VARIABLE]
CARRIAGE BOLT JUST LONG
ENOUGH TO REACH POINT A
NYLON WASHER
IFOR WOOD POST SUPPORTS»
SPECIAL TOOL NO 2
МШ
ALUMINUM FLUTED NUT5 (FOR ALUMINUM DELINEATORS
AND SIGNS ON U — CHANNEL POSTS)
BLIND ALUMINUM RIVETS (FOR ALUMINUM AND 13
PLYWOOD SIGNS ON
U-CHANNEL POST9)
FIGURE 7.56 Teenut, aluminum fluted nut, and blind aluminum rivet sign fasteners.
7.8 MAINTENANCE OF TRAFFIC SIGNS
Continuing maintenance is required to ensure that traffic signs function for their intended purpose. Proper maintenance of all signs is important since the condition of the signs is a visual statement on the competency of the roadway agency. Regulatory and warning signs that are missing or in poor condition pose safety hazards to
motorists and can result in tort liability. Regulatory and warning signs must be repaired as soon as a defect is noticed. All of the signs on an agency’s roadway system should be inspected periodically to determine that their orientation and retroreflectivity properties are adequate for nighttime visibility.
Damage to traffic signs can occur as the result of environmental and wind load, accidents, improper installation, end of effective service life, and vandalism. Repairs can be required for the sign panel, the sign support, or both.
