The Consumer Product Safety Commission has voted to restrict allowances given to unblockable drain covers in the federal pool and spa safety law.

On Wednesday, CPSC’s voting commissioners decided to change the definition of an unblockable drain to require that the sump, in addition to the drain cover, measure more than 18 by 23 inches and meet certain other testing criteria.

The measure passed 3 to 2, in what some say was a predetermined outcome.