Material Description. This specification covers the requirements for a closed cell, foam-in-place thermoplastic material to be used as a seal against air, dust, and water. The material may also be used for certain applications as a gasket or rattle isolator. Materials meeting the requirements of this specification will be comprised of two (2) classes and several types. 

• Class l: Materials will be used for air, dust and rattle isolators. 
• Class II: Materials will be used for water sealing and must meet the water impermeability requirements of this document. Materials are divided into types, depending on chemistry. 
• Type I: Thermoplastic Rubber Based Material. 
• Type II: Thermoplastic Urethane Based Material. 
• Type III: Other technology to be called out on drawing. 

Symbols. Not applicable. 

Applicability. Materials to be used as air and dust seals or water seals and gaskets in the body area and for rattle protection and other suitable applications. 

Remarks. 

The material must not stain, attack, or have any other objectionable effect on adjacent surfaces. 

This material is foamed through the introduction of an inert gas, such as nitrogen, carbon dioxide, or compressed air to a specific density reduction. The material is allowed to cool with the gas bubbles intact and a closed cell foam product is formed. Density reduction denotes the percentage of inert gas content. The amount of density reduction/gas content must be specified on the drawing.