Nitrogen-Blown Foam Used in Proximity Suit For Better Heat Shield
The problem of shielding fire fighters from radiant heat and hot air has been attacked through the introduction of fire-proximity suits made of aluminized film bonded to plastic to aluminum to rayon and attached to layers of nitrogen-blown foam.
Protection, Incorporated, of Gardena, Calif., uses GenTex “Dual-Mirror” Mylar-backed aluminized fabric and mounts it on a removable liner of nitrogen-blown vinyl foam to cut heat transfer to the wearer. This foam is then integrally sewn to a heavy cotton poplin.
In tests by crash crews, “Fire Shield” proximity suits were subjected to 24-hour duty for one year. During that time, these suits enabled firemen to approach fires with considerably more comfort than with conventional equipment.
“In a recent fire,” said Robert J. Zimmerman, Protection’s general manager, “two firemen in our suits were able to work the fire from a distance of only 2 feet. A fireman in a conventional suit could get no closer than 20 feet.”
The two major reasons for losing reflectivity—and thereby cutting down suit life—are dirt and abrasion. In drycleaning or washing to maintain reflectivity, Mylar shows superior characteristics, it is reported. The cloth manufacturer claims that abrasion-resistance is increased when aluminum is bonded to a tough plastic, which is not easily deformed as the fabric is creased or rubbed against hard or sharp objects.