A unique phase change material composition and method of maintaining pre-established environmental conditions and safeguards during the manufacturing process. A fabrication method and parameters which result in a more efficient and safe packaged phase change material. A microspherical form of Perlite is the chosen phase change material. The microspherical form of Perlite is vacuum packed in such a manner to exclude water and moisture as well as utilizing a sealing surface of sufficient width to maintain a vapor barrier at the sealed edges. Besides absorption and release of heat, the packaged phase change material may be used as a fire preventive article in residential and commercial properties.