United States Fire Administration:
Because both ionization and photoelectric smoke alarms are better at detecting distinctly different yet potentially fatal fires, and because homeowners cannot predict what type of fire might start in a home, the USFA recommends the installation of both ionization and photoelectric or dual sensor alarms.
USFA Statement on Smoke Alarms, May 2008
The International Association of Fire Chiefs:
Since it cannot be predicted what type of fire will start in a home, it is important that both smoldering and flaming fires are detected as quickly as possible. The best protection is to have both types of smoke alarms installed, or install dual sensing technology smoke alarms that incorporate both ionization/photoelectric sensors.
IAFC 'Smoke Alarms – Ionization and Photoelectric Technology Position Paper,' revised April 2008
National Fire Protection Association:
Smoke alarms using either ionization or photoelectric smoke detection technologies, installed per NFPA 72-2007, are generally providing acceptable response to smoldering fires. More tests are needed regarding photoelectric alarm’s response in flaming scenarios.
'Smoke Technology Report: Recommendations,' NFPA 72 Task Group, February 2008
National Association of State Fire Marshals:
Early detection of fires is crucial to escape time, because the time to untenable conditions in residences can be as little as 3 minutes for typical flaming fire scenarios. Both ionization and photoelectric smoke alarm technologies quickly alert occupants in most fire scenarios… To ensure that both smoldering and flaming fires are detected as quickly as possible, the best protection is to have both types of alarms installed, or dual ionization/photoelectric alarms.
Statement on Ionization and Photoelectric Smoke Alarms, April 2006
National Institute of Standards and Technology:
Smoke alarms of either the ionization type or the photoelectric type consistently provided time for occupants to escape from most residential fires.… Consistent with prior findings, ionization type alarms provided somewhat better response to flaming fires than photoelectric alarms, and photoelectric alarms provided (often) considerably faster response to smoldering fires than ionization type alarms.... Smoke alarms of either type installed on every level generally provided positive escape times for different fire types and locations.
Performance of Home Smoke Alarms: Analysis of the Response of Several Available Technologies in Residential Fire Settings, NIST, February 2008 Revision
Consumer Product Safety Commission:
Because both ionization and photoelectric smoke alarms are better at detecting distinctly different yet potentially fatal fires, and because homeowners cannot predict what type of fire might start in a home, CPSC staff recommends consumers install both ionization and photoelectric type smoke alarms in their home.
CPSC.gov, March 2008
Underwriters Laboratories (UL):
While photoelectric smoke alarms generally respond faster to smoldering smoke conditions and ionization smoke alarms generally respond faster to flaming fire conditions, both types provide adequate protection against fire. Combination smoke alarms featuring both photoelectric and ionization technology are also available at hardware, department and home improvement stores.
UL.com
Consumers Union (publisher of Consumer Reports):
Consumers Union, the nonprofit publisher of Consumer Reports, recommends you install smoke alarms with two different types of sensors: Ionization sensors ($10 and up) are better at detecting fast, flaming fires. Photoelectric sensors ($15 and up) are better at detecting smoldering fires. Your best bet is to buy dual-sensor alarms ($25 and up), which contain both detector types.
ConsumerReports.org, March 2007 , March 2007
Home Safety Council:
For the best detection and notification protection, install both ionization- and photoelectric-type smoke alarms.
HomeSafetyCouncil.org