Buyer Beware - Ionization smoke alarms perform poorly in real world fires.
On November 18, 2014, the Consumer Products Safety Commission for the first time publicly acknowledged that current smoke alarms only have a 45% to 49% overall alarm success rate and supported significant changes to the UL 217 alarm testing standards. This does nothing to help the 100+ million US homes with existing ionization alarms. Nor does it require notifying the public as to the known limitations of ionization technology alarms.
credit ASHI for information