Laminar flow hoods are essential machines to medical research. They are an enclosed worktop that scientists can keep entirely sterile. In the hoods, scientists can do various treatments on cells or experimental animals, keeping both the test subjects safe from outside contaminants, and scientists safe from possible threats inside the hood, like virus particles. However, they require strict maintenance to ensure the region inside the hood remains sterile and safe.
Laminar flow hoods are equipped with filters that trap particles that might flow into the hood and contaminate the air in the sterile environment. These filters, ranging from basic air filters to the more complex high efficiency particulate air , or HEPA, filters, must be changed on a regular basis to ensure they are effective. Each type of filter has a different lifespan. For example, HEPA filters can last from 3 to 5 years. Filters should be marked so that you know when to change them.
Most of the front of the flow hood is protected by a sliding glass door that lifts to allow a scientist to reach in his or her hands. When the window is lifted up, a blower begins to push air out, creating a barrier that stops environmental air from getting into the sterile hood. The blower is an essential part of the flow hood's effectiveness. Regular check ups to ensure that is blowing at a steady, strong rate are necessary. Most research institutions have a scheduled cycle for flow hood blower maintenance in order to keep them in working order.
Each time a researcher uses the hood, they need to make sure the surfaces within it are cleaned. Strong acids and bases can eat away at the metal or acrylic that covers the worktop and walls, and must be cleaned immediately. To keep the area free of bacteria or other foreign contaminants, cleaning with a fast-evaporating alcohol, such as an ethanol mixture, is the best way to keep the surfaces sterile.