State rules or regulations that require 24 hour maintenance of temporary traffic warning devices along highway work zone

Arizona DOT’s Standard Specifications basically state that the contractor’s is responsible for traffic control and will be available at all times to maintain the traffic control devices. This is highlighted below:
701-3 Construction Requirements:
701-3.01 General:
The contractor shall provide for the adequate protection of all vehicular and pedestrian traffic and workers through any portion of the work where construction operations interfere with, obstruct, or create a hazard to the movement of traffic.
At the pre-construction conference, the contractor shall provide the engineer with the name of the contractor’s employee who is responsible for implementing, monitoring, and altering, as necessary, the traffic control plan. The engineer will then advise the local law enforcement agency having jurisdiction of the names of the contractor’s representative and a representative of the Department who will act in a similar capacity. The contractor’s designee shall be available at any time to respond to calls involving damage or displacement to barricades, lights, signs, and other devices resulting from vandalism, traffic accident, or other causes.
If, at any time, the engineer determines that sufficient traffic control is not being provided or maintained, the engineer may order suspension of the work until the proper level of traffic control is achieved. In cases of serious or willful disregard for safety of the public or workers by the contractor, the engineer may proceed to place the traffic control measures in proper condition and deduct the cost thereof from monies due or becoming due the contractor.