A new generation of smoke alarms and smoke detectors is on the way. Based on major changes to the product Standards incorporating more than 10 years of research, new devices will be tested to ensure that they are  more responsive to smoldering and flaming fires from polyurethane (PU) foam, now ubiquitous in fabric and furniture, while slowing activation from common cooking sources that have been the cause for nuisance alarms.

The objective is to keep smoke alarms installed and working and to be sure that they respond to the kind of fires most likely in today’s households.

The most common reason that smoke alarms are disabled is because of nuisance alarms from cooking. The new tests require that the devices don’t respond too quickly to the types of smoke particles generally given off during normal cooking activities such as pan-frying, baking, or sautéing.

Research also confirmed that the smoke particle size and color given off by PU foam fires was different from those generated by natural materials, so the test fires now include two using PU foam.

These new requirements apply to smoke alarms that are battery-operated or AC powered with battery backup, common in most households, and also smoke detectors that are connected to a control unit and used in some residential and most commercial installations. Products are required to be tested by a nationally recognized testing laboratory (NRTL) that is U.S. Occupational Safety and Health Administration (OSHA) accredited to test to ANSI/UL 217, Standard for Single and Multiple Station Smoke Alarms, and smoke detectors to ANSI/UL 268, Standard for Smoke Detectors for Fire Alarm Signaling Systems. Underwriters Laboratories and Intertek Testing Services are approved to test to both Standards. (While FM Global can test UL 268 products, they did not, at the time of this writing, have plans in place to test to the 7th edition of the Standard.)

Testing by the Consumer Product Safety Commission, the National Institutes of Standards and Technology, the Fire Protection Research Foundation, and Underwriters Laboratories were all important to developing the new requirements.

Products meeting the new Standards are already available and will continue to flow into the market over the coming months.

Current alarms and detectors do not need to be replaced unless, in the case of smoke alarms, they have reached their end of life of 10 years since the date of manufacture.  As with other changes to Standards, products already installed, manufactured and in inventory remains listed and safe to install and continue using.

Each testing laboratory sets its own effective date. Products manufactured to carry the UL listing mark after June 30, 2021, will have to comply with the new Standards. The ETL Mark’s compliance date is December 31, 2021. Earlier dates that were previously announced were changed based on lab capacity and testing capabilities.

While the cooking nuisance resistance and PU foam response is the most dramatic change, there were several hundred changes to the Standards. For smoke alarms, one of the most noticeable will be a required “end of life” signal. This will sound when the alarm needs to be replaced, at a maximum of 10 years.

NFPA 72®, the National Fire Alarm and Signaling Code, mandates devices to be installed;

  • In all sleeping rooms and guest rooms
  • Outside of each separate dwelling unit sleeping area, within 21 ft (6.4 m) of any door to a sleeping room, with the distance measured along a path of travel
  • On every level of a dwelling unit, including basements
  • On every level of a residential board and care occupancy (small facility), including basements and excluding crawl spaces and unfinished attics
  • In the living area(s) of a guest suite
  • In the living area(s) of a residential board and care occupancy (small facility)

Further, the smoke alarms shall be interconnected so that when one sounds, they all go into alarm mode. This is not, however, universally required or enforced, and some households have only one. Or, if they have more, the alarms may not be interconnected.

While several jurisdictions now require battery-operated alarms to be sealed, 10-year devices, most allow certain exceptions. Smoke alarms, including wireless interconnection, for example, can use replaceable batteries in order to make it possible to retrofit interconnection without hardwiring.