Inside Report (5)

TV networks aren't the only ones chasing higher ratings this fall.

Some key labor unions are following the lead of AFSCME, the public employees union, which ran a TV ad with a nurse pushing a wheelchair, saying, ''We're losing experienced people, and it's very discouraging.''

Now at least three others are jumping on the ad wagon. The National Education Association, a teachers union, recently began a $1.5 million advertising effort on ABC and NBC. The American Postal Workers launch their ads in mid-October. Also experimenting with TV: the United Auto Workers.

AFSCME will be back this winter with a new $2.5 million effort. The union found a 15 percent improvement in public acceptance after its 1982 campaign, according to a follow-up poll.

California has been targeted for the largest chunk of next year's AFSCME ad spending - $1 million. Reason: The union is trying to organize 70,000 workers in the state university system there.