28 Miss. Code R. § 305-2.20
The Mississippi State Port Authority absolutely prohibits any form of substance abuse by employees while on Port Authority premises or while conducting Mississippi State Port Authority business. For this purpose, substance abuse means use, possession, sale, manufacture, distribution, dispensing, or being under the influence of unauthorized drugs or alcohol on Port Authority premises, in Port Authority vehicles, or while on Mississippi State Port Authority business. Employees may maintain prescription drugs on Mississippi State Port Authority premises provided the drugs have been prescribed by a physician for the person in possession of the drugs. Employees should notify their supervisor concerning the possession of prescription drugs. Provided that an employee is not driving a vehicle, an employee may consume a moderate amount of alcoholic beverages associated with public relations, marketing, or official business activities and events.
28 Miss. Code. R. § 305-2.20