Like we suggested in the previous point, wipe down your working surface of the hood with 70% IPA or ethanol and also wipe everything that gets inside the hood, including your glove-wearing hands. Remove rings and other ornaments on your body before working in a cell culture lab. Also avoid talking unnecessarily or touching your skin or hair while inside the culture room. All these may sound cliché and trivial but every small step helps in reducing the chance of bringing contaminants from outside in the form of aerosols or microbial contaminants. Avoid moving things in and out of the hood while working on your cell culture and always plan your experiments ahead.