(A) When utility, street maintenance or repair or construction operators are working on or adjacent to the traveled way, it is the responsibility of said work crews to adequately protect and control traffic.
(B) Adequate traffic protection is defined in the Iowa Manual on Uniform Traffic Control for Streets and Highways, or as a minimum shall be:
(1) Through streets with speeds of 45 mph or greater, lights and/or signs, cones and barricades. Flaggers at either end of operations are also required when operations are on the traveled way;
(2) Through streets with speeds of less than 45 mph, lights and/or signs. When operations are on the traveled way, barricades and/or flaggers are also required; and
(3) Residential and other streets, lights or signs. Flagging should be provided at periods of unusual traffic.