The relative humidity in an incubator is usually set at 40% to 60%. This is because incubators are used to provide a controlled environment for the growth and development of organisms, such as bacteria, fungi, and cells. Maintaining the proper humidity level is essential to ensure that the organisms can grow and reproduce under optimal conditions.
If the humidity is too low, the organisms may dry out and die. On the other hand, if the humidity is too high, excess moisture can lead to the growth of unwanted microorganisms, such as mold or bacteria, which can negatively impact the growth of the desired organisms.
Therefore, a relative humidity range of 40% to 60% is considered ideal for most organisms, as it provides enough moisture to support their growth and development, without creating conditions that promote the growth of unwanted microorganisms.