Testifire generates its non toxic smoke stimulus from a specially formulated,
fluid supplied in a replaceable non pressurized capsule. The number of tests
from a capsule is dictated by the response time of the detectors under test and
can range between 500 and 1,000 tests. Although there is much more to the
comparison than material cost, typically this equates to between two and five
times that produced by an aerosol.
Link to TC3 Carbon Monoxide Capsule (TC3)