epdm

Ethylene Propylene Diene Monomer. A single ply membrane consisting of synthetic rubber; usually 45 or 60 mils. Application can be ballasted, fully adhered or mechanically attached.
Found on http://www.encyclo.co.uk/local/21074

EPDM

Ethylene Propylene Dione Monimer. This is a synthetic rubber compound used as insulation in making electrical components.
Found on http://www.youngco.com/young2.asp?ID=4&Type=3
No exact match found