From N.F.P.A. Pamphlet 72, National Fire Alarm Code, 2002 Edition:

10.4.3.2*   Sensitivity of smoke detectors and single- and multiple-station smoke alarms in other than one- and two-family dwellings shall be tested in accordance with 10.4.3.2.1 through 10.4.3.2.6.

10.4.3.2.1   Sensitivity shall be checked within 1 year after installation.

10.4.3.2.2   Sensitivity shall be checked every alternate year thereafter unless otherwise permitted by compliance with 10.4.3.2.3.

10.4.3.2.3   After the second required calibration test, if sensitivity tests indicate that the device has remained within its listed and marked sensitivity range (or 4 percent obscuration light gray smoke, if not marked), the length of time between calibration tests shall be permitted to be extended to a maximum of 5 years.

10.4.3.2.4   To ensure that each smoke detector or smoke alarm is within its listed and marked sensitivity range, it shall be tested using any of the following methods:
(1) Calibrated test method (2) Manufacturer's calibrated sensitivity test instrument (3) Listed control equipment arranged for the purpose (4) Smoke detector/control unit arrangement whereby the detector causes a signal at the control unit where its sensitivity is outside its listed sensitivity range (5) Other calibrated sensitivity test methods approved by the authority having jurisdiction.

10.4.3.2.5   Detectors or smoke alarms found to have a sensitivity outside the listed and marked sensitivity range shall be cleaned and recalibrated or be replaced. Exception: Devices listed as field adjustable shall be permitted to be either adjusted within the listed and marked sensitivity range and cleaned and recalibrated, or they shall be replaced.

110.4.3.2.6   The detector or smoke alarm sensitivity shall not be tested or measured using any device that administers an unmeasured concentration of smoke or other aerosol into the detector or smoke alarm.