Curve warning sign study

This report determines how curve warning sign guidelines are being interpreted and implemented by districts in California. Generally, district traffic engineers consider the existing criteria for curve warning signs and advisory speed plates in Chapter 4 of the Traffic Manual to be adequate directions for their use. The policies provide enough general direction to allow engineers to design specific sign installations that will be uniformly understood by the public. The largest difference in sign application occurred with the W14 sign and its repetition within a winding highway section. This report suggests that this sign is not as effective as believed.