Describe two tools used for maintaining aseptic conditions

1.The Bunsen Burner
· Probably the easiest way to create a relatively sterile environment on the laboratory bench is by using a simple gas powered burner.
· This common piece of equipment burns a continuous stream of a flammable gas—usually natural gas (methane)—based upon a design made almost 150 years ago by the German chemist Robert Wilhelm Bunsen (1811-1899).
· A major purpose of the open flame in aseptic technique is to create a cone of hot air above and around the laboratory bench to reduce the viability of organisms on suspended dust particles. · The ability of the Bunsen burner flame to heat things very quickly also makes it an ideal choice for sterilizing inoculating loops, warming glass bottle necks, or igniting alcohol on culture spreaders. · A Bunsen burner is not practical in some situations, e.g., within a laminar flow unit where the heat will disrupt airflow.
· A micro incinerator may be used as an alternative. This consists of a circular heating element. Placing an inoculating loop or needle within the ring will quickly heat and sterilize the loop/needle. · Note that a micro incinerator does not provide other aseptic technique benefits of a lit Bunsen burner.

2.The Laminar Flow Unit
· A laminar flow unit (or hood) is a sophisticated appliance that can further help prevent contamination of reagents and biological cultures.
· Used correctly, it provides the work space with clean, ultra filtered air.
· It also keeps room air from entering the work area and both suspends and removes airborne contaminants introduced into the work area by personnel.
· The most important part of a laminar flow hood is a high-efficiency bacteria-retentive filter, i.e., the HEPA (high-efficiency particulate air) filter.
· A certified HEPA filter must capture a minimum of 99.97% of dust, pollen, mold, bacteria, and any airborne particles with a size of >0.3 µm at 85 liters/min.
· The first HEPA filters were developed in the 1940s by the U.S.A. Atomic Energy Commission as part of the Manhattan Project (the development of the atomic bomb) to provide an efficient, effective way to filter radioactive particulate contaminants.
· HEPA filter technology was declassified after World War II, allowing extensive research and commercial use.
· Laminar flow hoods are essential components of many biosafety level (BSL)-2 laboratories, where they help prevent spread of viruses and some bacteria.

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Titany answered the question on September 10, 2021 at 12:29