Here is some additional information:
NFPA 72, Fire Alarm Code:
10.4.5 Household Fire Alarm Systems.
10.4.5.1 Testing. Household fire alarm systems shall be tested by a qualified service technician at least every 3 years according to the methods of Table 10.4.2.2.
10.4.5.2 Maintenance. Maintenance of household fire alarm systems shall be conducted according to manufacturer’s instructions.
10.4.6 Replacement of Smoke Alarms in One- and Two-Family Dwellings.
Unless otherwise recommended by the manufacturer, single- and multiple-station smoke alarms installed in one- and two-family dwellings shall be replaced when they fail to respond to operability tests, but shall not remain in service longer than 10 years from the date of manufacture.
10.4.7 Battery Replacement.
Where batteries are used as a source of energy, they shall be replaced in accordance with the recommendations of the alarm equipment manufacturer.
