Keep vials upright within jars. Each jar should be filled with alcohol to just below the level of the gasket. If material is going to be stored for long periods of time, the jars should be checked periodically and the alcohol topped off. Labels may also be placed on the outside of the jars to indicate the enclosed contents. Light is the chief enemy of alcohol preserved material, and as a result, jars should be stored inside cabinets.
Fire safety is always an important consideration when storing or working with alcohol collections.
Concentrations of vapors can be very hazardous so care should be taken that work areas are properly ventilated and that there is no source of open flame nearby. In larger collections, special cabinets, exits, and other precautions may be necessary to meet the fire code. Preservation for Molecular Studies Systematists are increasing using molecular methods to study insect relationships, make identifications, and determine species limits. Some of these techniques, such as study of cuticular hydrocarbons, can be used on dried insects, even those stored in museum collections. However, many others require that specimens be treated so that DNA or other molecules are preserved.