6Storage and handling of signs#

6.1General#

In order for the sign to be effective, the surface of the sign must be free from damage, abrasion, dirt, oil or other markings causing loss of legibility. These problems are especially severe when dealing with reflective material, since night-time legibility is directly related to the quality and clarity of the reflective surface.

6.2General storage#

Signs should be stored vertically on edge, either in a rack or in such a way that they are supported vertically. Damage is likely to occur to signs stored in contact with each other, or banded together. Signs stacked tightly together result in pressure points being induced on the reflective sheeting faces, leading to areas not reflecting.

6.3Indoor storage#

Signs stored indoors may be left in their original transport packaging, provided that the storage area will be maintained at a constant room temperature and is well ventilated. However, the banding around any sign should be cut and removed. If the storage area is a small, non-ventilated area, signs should be unwrapped from their transport packaging (that is, cardboard, bubble wrap, and so on) and only stored for relatively short periods.

6.4Outdoor storage#

Signs stored outdoors must be unwrapped from their transport packaging and stored upright, on edge, using wooden battens on the floor, or as vertical supports, or both. Signs stored outdoors, especially large direction signs, should be stored using a racking system, providing vertical support, avoiding pressure points on sign faces and allowing adequate air circulation between sign faces to prevent a build-up of moisture.

6.5Sign transport#

When transporting signs by truck or trailer, it is imperative that signs be securely braced vertically, and adequately supported and secured to avoid damage due to scuffing, abrasion and load shifting. Large direction signs should be braced using wooden stiffeners attached to the extrusions at the back of the sign, and transported with the stiffeners in place to avoid buckling and rivet popping.

6.6Sign erection#

Once signs have been transported to the road site, they should not be laid flat on the ground. Laying signs flat, can result in damage to the reflective face through direct contact with the ground. When attaching signs to posts, all connecting bolts should be tightened using offset spanners, not socket wrenches. The use of offset spanners minimises tool and hand contact with the sign face and avoids scratching of the surface, as well as allowing the extent of tightening to be observed. Only one end of the nut and bolt should be tightened, preferable tightened from the rear of the sign. Tightening from both sides can transfer stress into retroreflective sheeting, with a top film resulting in permanent pinwheel style wrinkles.

Avoid over-tightening the connecting bolts, as this can cause specular glare from dimples on the sign face. Nylon washers should be used between connecting bolt heads and the sign face, to protect the reflective sheeting from the twisting action of the bolt heads. A circle of diameter slightly larger than the bolt head may be scored in the reflective sign face around the bolt hole, to minimise any fine cracking that may inadvertently occur during bolt tightening. When erecting large Direction signs, care must be taken to prevent lifting ropes, cables and chains from contacting the sign surface. These can cause permanent visible damage. After installation, and before leaving the road site, inspect all signs to see that they have not been damaged during erection and are free of oil and dirt residue from fingers and tools. A night inspection will confirm that the surface has not been damaged.

6.7Sign covering#

Covering signs is not recommended. If it is necessary to cover a sign face temporarily after erection, caution must be exercised, as some coverings may cause permanent damage to the sign face following exposure to moisture and sunlight. Porous cloth covers, which are folded over the sign edges and secured to the back of the sign, have been used successfully for limited periods. Avoid the use of ropes, wire fasteners or strapping that may abrade the sign surface. Do not apply tape to the sign face, as sunlight will cause it to bond permanently. Premask or application tape must be removed before exposure to sunlight. Do not use paper or plastic covers as heat and moisture entrapment can cause permanent damage to the reflective sheeting on the sign face. Consult the sign sheeting manufacturer for advice on how to appropriately cover the sign face to maintain the product warranty.

6.8Sign cleaning#

For maximum performance, signs should be kept clean and free from dirt, road tar, oil, bituminous material and mulch. Primarily, this means cleaning the surface of the reflective sheeting – the essential characteristic of a sign. A wet, detergent-type, non-abrasive cleaner suitable for high quality paint surfaces is recommended. The cleaner must also be free of strong aromatic solvents or alcohols and be chemically neutral (that is, pH of around 7.0). Following use of any cleaning agent, the sign surface must be thoroughly and immediately rinsed with clean water. In all cleaning operations, care should be taken not to abrade the sign by use of stiff-bristle brushes or by unnecessary scrubbing. Normal cleaning procedure:

1. 1)Flush the surface with clean water to remove loose, dirt particles. A squeeze (or triggered) hose nozzle is convenient for this purpose.
2. 2)Wash the sign face with a rag or sponge using a suitable detergent or commercial cleaner. Wash thoroughly from the top down. Once suds have been applied, keep a steady stream of water flowing on the sign face to wash away dirt particles.
3. 3)Rinse the entire sign face with clean water and allow the sign to drain dry.
4. 4)Take extreme care in cleaning screened sign faces since some cleaning solvents may damage the screen print.

Use a mild solvent such as mineral spirits for cleaning the sign face. Follow with detergent and water, then rinse with clean water. Avoid high-pressure sprayers. Do not direct sprays at sign face edges.