Standard method for deposition of dry, aerosolized, silica‐coated Bacillus spores onto inanimate surfaces

Aims To evaluate a standard aerosolization method for uniformly depositing threat‐representative spores onto surfaces. Methods and Results Lyophilized Bacillus anthracis ΔSterne spores, coated in silica, were aerosolized into a containment chamber and deposited onto nine surface types by two independent laboratories. Laboratory A produced a mean loading concentration of 1·78 × 105 CFU cm−2; coefficient of variation (CV) was