Two dozen pictorial painters, electricians, carpenters and representives of the Rollins Outdoor Advertising Co. told the Prince George's County Council yesterday they might lose their jobs should the council pass a law limiting the size and placement of billboards in the county.

A Bill sponsored by council members Parris N. Glendening and Frank Casula would limit a billboard to 400 square feet and 35 feet in height. It would also require 1,000 feet between billboards on the same lot and a 200 foot setback from the street. Under existing law, a billboard can have up to 1,000 square feet with no height restrictions.

Rollins general manager Vincent J. Ernano called the billboard restrictions " not regulation, just prohibition. "

Glendening told Ernano that the bill " does not outlaw billboards, it just limits them. Fast food stores, billboards, all affect the quality of life in this county. If you buy a nice home in a good neighborhood and you go two blocks and see one of those giant signs, it's nothing but blight. The public supports me on this issue. "

One Rollins employe told the council, " IIf you vote this bill in, I don't know what will happen to me and my family. It will cut down on our adventising and will cut down on my pay check. "

The council is expected to act on the bill next Tuesday.