Evaluation of surface sampling for Bacillus spores using commercially available cleaning robots

Area of Science:

• Environmental Science
• Microbiology
• Robotics Engineering

Background:

• Effective sampling of microbial contaminants like Bacillus atrophaeus spores is crucial for indoor environmental quality assessment.
• Traditional surface sampling methods may have limitations in efficiency and ease of use.
• Domestic cleaning robots offer a potential alternative for surface sampling due to their autonomous operation.

Purpose of the Study:

• To evaluate the efficacy of five different domestic cleaning robots in sampling aerosol-deposited Bacillus atrophaeus spores.
• To compare the performance of these robots against conventional surface sampling techniques (vacuum sock and sponge wipe).
• To assess the potential for spore resuspension during robotic sampling.

Main Methods:

• Five commercial robots (three vacuum, one wet wipe, one wet vacuum) were tested.
• Bacillus atrophaeus spores were deposited on carpet and laminate surfaces within an isolation chamber.
• Robot sampling efficacy was measured relative to standard methods, and air sampling monitored for spore resuspension.

Main Results:

• On carpet, vacuum robots (R1, R2, R3) achieved 26%, 162%, and 92% of vacuum sock sampling efficacy, respectively.
• On laminate, robots (R1, R2, R3, R4, R5) achieved 8%, 11%, 2%, 62%, and 32% of sponge wipe sampling efficacy, respectively.
• Spore resuspension during sampling was monitored via air sampling.

Conclusions:

• Certain domestic cleaning robots can be as effective as traditional methods for sampling Bacillus atrophaeus spores on carpet and laminate.
• Robotic cleaners present a viable option for microbial surface sampling in indoor environments.
• Further research may explore optimizing robotic sampling strategies for various indoor surfaces and microbial agents.