It is desirable to place laboratory instruments in static storage so that they may be put into operation with only normal servicing. Such instruments may be subject to many forms of deterioration. There may be deterioration of metal parts due to chemical and electrolytic corrosion and the effects of moisture, excessive dryness, and microorganisms, i.e., mildew on organic parts. To preserve such instruments without disassembly or troublesome surface coatings, requires methods that will remove the major cause of deterioration - that is, excessive humidity, by reducing and maintaining the relative humidity of the air surrounding the item at 30 per cent or less. It is also necessary to eliminate or separate hygroscopic materials from the item since they will cause corrosion, by surface adsorption and condensation, even though a dry atmosphere is maintained. The methods and materials used must not only be efficient and economical but also require a minimun of maintenance, Protection against physical damage and temperature extremes is dependent upon the storage site and is not considered in this report.