Streaking of plates In general, aerosol production is minimized by using smooth plates. Rough surfaces or bubbles in the agar can lead to exces- sive vibration of the loop. Spreading of samples with a sterile glass rod may minimize the production of aerosols on agar plates with rough surfaces Pouring of Microbial Suspensions Following centrifugation, pouring off the supernatant from a microbial suspension can result in aerosols. One safe way to min imize aerosol production is to use a funnel with the narrow end submerged into disinfectant in a large container. Use enough disinfectant to mediate the decontamination of the supernatant and a container large enough to avoid overflow. A volume of disinfectant equal to, or greater than, the amount of supernatant to be decontaminated should suffice. Rinse the funnel with more disinfectant to handle any residual supernatant clinging to th funnel wal Even for solutions deemed to be safe, it is good practice to never mouth pipette. It is mandatory not to mouth-pipette a microbial solution, even with a cotton-plugged pipette. Aspiration of organisms into the mouth can occur despite the cotton plug Blowing out the last few droplets from a pipette can also form aerosols. Use either a manual or automatic pipetting aid to pipette. The discharge of the last few droplets using either manual or automatic pipette aids can result in aerosols, so avoid this if possible. If it is necessary to discharge the entire contents of pipette, try to avoid spraying. Again, for serious pathogens, pipet ting should be performed in a biosafety hood. Contaminated pipettes should be discarded into a container containing a suffi cient volume of disinfectant to permit the complete immersion of the pipette Are You Prepared to Deal with an Emergency Adequate preparation for an emergency requires both an appreciation for the potential hazards involved and knowledge of the resources available to handle the emergency. Such ration should precede actual lab work, although this is rarely done We have discussed the appropriate types of laboratory clothing that should be worn in the microbiology laboratory, important safety equipment and supplies, and potential sources of harm 122 Haidaris and BrownlowStreaking of Plates In general, aerosol production is minimized by using smooth plates. Rough surfaces or bubbles in the agar can lead to exces￾sive vibration of the loop. Spreading of samples with a sterile glass rod may minimize the production of aerosols on agar plates with rough surfaces. Pouring of Microbial Suspensions Following centrifugation, pouring off the supernatant from a microbial suspension can result in aerosols. One safe way to min￾imize aerosol production is to use a funnel with the narrow end submerged into disinfectant in a large container. Use enough disinfectant to mediate the decontamination of the supernatant, and a container large enough to avoid overflow. A volume of disinfectant equal to, or greater than, the amount of supernatant to be decontaminated should suffice. Rinse the funnel with more disinfectant to handle any residual supernatant clinging to the funnel wall. Pipetting Even for solutions deemed to be safe, it is good practice to never mouth pipette. It is mandatory not to mouth-pipette a microbial solution, even with a cotton-plugged pipette. Aspiration of organisms into the mouth can occur despite the cotton plug. Blowing out the last few droplets from a pipette can also form aerosols. Use either a manual or automatic pipetting aid to pipette. The discharge of the last few droplets using either manual or automatic pipette aids can result in aerosols, so avoid this if possible. If it is necessary to discharge the entire contents of the pipette, try to avoid spraying. Again, for serious pathogens, pipet￾ting should be performed in a biosafety hood. Contaminated pipettes should be discarded into a container containing a suffi- cient volume of disinfectant to permit the complete immersion of the pipette. Are You Prepared to Deal with an Emergency? Adequate preparation for an emergency requires both an appreciation for the potential hazards involved and knowledge of the resources available to handle the emergency. Such prepa￾ration should precede actual lab work, although this is rarely done. We have discussed the appropriate types of laboratory clothing that should be worn in the microbiology laboratory, important safety equipment and supplies, and potential sources of harm. 122 Haidaris and Brownlow