When exposed to high relative humidity, such familiar foods as potato chips, dry breakfast cereals, and soda crackers exhibit an affinity for water. These and similar foodstuffs are manufactured using high temperature processes, so we expect that excess water has been driven out and the foods are dry. However, if these foodstuffs are allowed to remain exposed in a humid environment, even for a short time, they will absorb water from the surrounding air. Although the quality is not affected, these foods characteristically become soggy and rubbery and generally not very appetizing.

In processing such powdery foods as cocoa, gelatin, and dehydrated concentrates, the presence of moisture in the surrounding atmosphere can cause tiny particles of the powder to stick or cluster together, thus inhibiting their free flow in manufacturing or packaging processes.

Processing machinery can also be affected by moisture in the air, which can interfere with operation and obstruct the free and easy movement of the foodstuff.

Obviously, when moisture can have such a profound effect on food and/or machinery, the solution lies in conditioning the air surrounding the processing and manufacturing area.

A hospital is a health care institution providing patient treatment with specialized medical and nursing staff and medical equipment. The best-known type of hospital is the general hospital, which typically has an emergency department to treat urgent health problems ranging from fire and accident victims to a heart attack.

There are various hospital equipment that should be protected the adverse effect of increased and decreased moisture. Bacteria will grow faster if the moisture is higher.

In many instances, moisture is detrimental to functioning of electrical or mechanical devices.Thousands of electrical relays may be threatened by pitting due to excessive arcing under high humidity conditions. Also, the presence of water vapor may corrode the contact points of infrequently operated electrical conductors resulting in poor closure of electrical circuits. In extreme cases, there may be no closure at all.

In other such places as radar stations and industrial applications, electronic equipment is also subject to loss of efficiency and high maintenance costs when exposed to humid conditions. And for work environments containing computers and other data processing
systems, humidity control is essential for assuring proper equipment function, Where practical, maintenance of dry enclosures may be necessary, Sometimes, it may be necessary to condition the equipment itself, since electrical operating devices are often enclosed in their own metal cases.

Frequently, the equipment used to package products will not function efficiently or properly if the surrounding air is humid. Candy wrapping machines and packaging machines for food powders or drug packets are typical examples.
Something as simple as a cake mix becomes a double problem; not only does the powdery mix clump and not flow properly in humid conditions, but the packaging equipment is also hindered by the humidity.

Depending on the product, it may be necessary to dry the packaging room and even go to the extreme of providing a dry bath for storage bins or hoppers, especially where powders are used. In situations where packages are heat-sealed, a container's own moisture content may adversely affect the adhesion of the sealing material being used. Here neither the product nor the machinery
is directly responsible for the problem; instead, the moisture content of the package is the culprit.
Surrounding the area with dry air is the solution.

Although mildew, rust, and corrosion are the enemies of goods in storage, they cease being threats when the moisture is substantially
reduced in the storage area. Generally, an atmosphere of less than 40% RH keeps these degradative processes dormant.
Maintaining a dormant state is also important for seed storage. For example, if corn seeds are stored in ambient conditions, it's possible that as few as 7% will germinate the following season. Contrast that to seeds stored in a controlled environment; they usually germinate in the 90% range.