Abstract: A system for spray coating a substrate such as a plastic container with a gas barrier coating of a polymer dispersion. The system includes a spray coating booth or chamber including spray nozzles dispensing a spray of a coating material onto the surface of a series of containers continuously moving into and out of the coating chamber, an oven for drying the wet coating to remove the water from the coating to form a dried film on the container without distorting the container, and a conveyor for transferring the containers into the coating booth into proximity to the spray nozzles such that on actuation of the nozzles a stream of coating material coats the surface of the bottles with a wet coating layer and, thereafter, to the oven where the wet coating is dried. Means are provided for rotating the bottles during coating, during transport between the spray coating booth and the oven, and while in the oven.