Radio Standards Specification 131 (RSS-131), Issue 3, Zone Enhancers, sets out certification requirements for zone enhancers used in conjunction with licensed radio equipment in certain radio services.

This standard came into effect as of January 19, 2017 for the purposes of certifying new equipment.

It should be noted that a transition period ending six (6) months following the publication of RSS-131, Issue 3, within which compliance with either RSS-131, Issue 3 or Issue 2, will be accepted. After which time, only compliance with RSS-131, Issue 3 will be accepted