It has been shown that acoustic fields, such as those experienced around the sounder horn and vent of smoke detectors when activated, enhances the agglomeration of aerosolised particles. In addition, there is an increase in particle interaction which causes an increase in the final agglomerate size. In practical terms this results in greater soot deposition on surfaces near to the sound producing parts of the smoke detector such as the sounder horn and vent.
We have experience of microscopically examining smoke detectors to determine if they sounded during a fire.
Thicker layer of soot particles around sounder horn
Thicker layer of soot around vents