Okla. Stat. tit. 47, § 47-14-105: Loads on vehicles

A. No vehicle shall be driven or moved on any highway unless

such vehicle is so constructed or loaded as to prevent any of its

load from dropping, sifting, leaking, blowing or otherwise escaping

therefrom, except that sand may be dropped for the purpose of

securing traction, or water or other substances may be sprinkled on

a roadway in cleaning or maintaining such roadway.

B. No person shall operate on any highway any vehicle with any

load unless said load and any covering thereon is securely fastened

so as to prevent said covering or load from becoming loose, detached

or in any manner a hazard to other users of the highway. Any

vehicle loaded with sand, cinders, or other loose material

susceptible to blowing or otherwise escaping shall have such load

covered so as to prevent the blowing or escaping of said load from

the vehicle.

C. This section shall not apply to trucks loaded with

livestock, poultry, hay or agricultural products, provided that any

such truck shall be so constructed or loaded as to prevent such

livestock, poultry or hay from escaping therefrom.