Extra advanced stovetop models have stress indicators that permit the user to regulate the heat to stop the steam from escaping. Third technology sorts mechanically measure the state of the vessel and management the ability so as to not release steam in operation. http://www.gymfan.com/link/ps_search.cgi?act=jump&access=1&url=https://moncountyhfh.org/news/ts04aq9l6g/