Okla. Stat. tit. 47, § 47-11-806: Special speed limitations

A. No person shall drive a vehicle over any bridge or other

elevated structure constituting a part of a highway at a speed which

is greater than the maximum speed which can be maintained with

safety to the bridge or structure, when the structure is signposted

as provided in this section.

B. The Oklahoma Department of Transportation and local

authorities may conduct an investigation of any bridge or other

elevated structure constituting a part of a highway, and if they

shall thereupon find that the structure cannot, with safety to

itself, withstand vehicles driving at speeds otherwise permissible

under Section 1-101 et seq. of this title, they shall determine and

declare the maximum speed of vehicles which the structure can safely

withstand, and may cause and permit suitable signs stating the

maximum speed to be erected and maintained at a distance of one

hundred feet before each end of the structure.

C. Where any state or federal highway or turnpike shall be

under construction, maintenance, or repair or when a detour shall

have been designated by reason of construction, maintenance, or

repairs in progress and a maximum safe, careful, and prudent speed

shall have been determined by the Oklahoma Department of

Transportation on the highway or highway detour or by the Oklahoma

Transportation Authority on the turnpike or turnpike detour during

the period of the construction, maintenance, or repairs and shall

have plainly posted by changeable message or other appropriate sign

at each terminus thereof and at not less than each half mile along

the route thereof the determined maximum speed, no person shall

drive any vehicle upon the portion of the highway or the highway

detour or upon the portion of the turnpike or the turnpike detour at

a speed in excess of the speed so determined and posted. Violation

of the posted speed limit in the repair, maintenance, or

construction zone shall result in the doubling of the appropriate

fine. For purposes of this section, "repair, maintenance, or

construction zone" means any location where repair, maintenance, or

construction work is actually in progress and workers present.

D. The Oklahoma Department of Transportation and the Oklahoma

Turnpike Authority may post, by changeable message sign or other

appropriate sign, a temporary reduced speed limit for special

hazards with respect to pedestrians, other traffic, an accident, by

reason of weather or when other hazardous highway conditions exist.

E. Upon the trial of any person charged with a violation of

this section, proof of the determination of the maximum speed by the

Department of Transportation or by the Oklahoma Transportation

Authority and the existence of the signs shall constitute conclusive

evidence of the maximum speed which can be maintained with safety as

provided in subsections B , C and D of this section.