The Consumer Product Safety Commission voted yesterday to initiate action that could lead to new restrictions or a ban on the sales of plastic lawn darts, which have been blamed in the deaths of several children.

The commission, voting 3 to 0, also directed its staff to "vigorously enforce" the current regulations prohibiting sale of the darts in toy stores or in boxes without warning labels.

Mary Ellen Fise, product safety director of the Consumer Federation of America, who had urged the commission to move immediately toward a ban on the darts, said, "We are more than a little bit disappointed. We hope that another child won't be made brain-dead before the action is completed."

The commission, which has come under congressional criticism for its failure to move against the darts, agreed to monitor the industry's compliance with five voluntary steps during the next three

months.

The steps, which CPSC officials suggested in an earlier meeting with industry officials, call for larger warning signs on boxes, warnings on the fins of individual darts, a change in design to prevent any modification of the darts, increased advice to merchants on how they should be sold, and an end of sales of darts in combination with other products.

"What the commission is saying is that we better see them {industry executives} moving on these five things in the next three

months," said Carl Belechschmidt, a manager of child and recreation program products at the safety commission.

Industry officials were divided over whether the agency should adopt mandatory or voluntary controls, he said. Under the Reagan administration, the commission has favored voluntary standards.