treated rather than salt-treated paper for facings. We are not talking about this year or next, but about 30 years from now when the mortgage is to be paid off-that is, if the home has not burned in the meantime as the result of unsafe methods of energy conserving insulation. When moisture is added to an insulating material, the insulating qualities become weakened and the public is shortchanged. Underwriters Laboratories brought to my attention that the Building Materials Directory states: "The loose fill materials, consisting of cellulosic fiber or shredded wood chemically treated to reduce combustibility, incorporate treatments consisting of water-soluble salts which may· be affected by repeated exposure to water or conditions that may result in the condensation of water." In the ERDA conclusions, it was stated that "Six of the 19 samples exceeded the moisture-absorption criteria of the standard specification when tested in a low-density configuration" as found in attic installations. Where corrosion was involved, 11 of the 19 samples used in the ERDA investigation showed corrosion rates greater than allowed under the ASTM Standard. Some showed extensive subsurface corrosion, particularly on aluminum. The sulfates appear to be the most critical where corrosion is concerned. ERDA also reported on fungal growth. Six of the 19 samples supported such growth. Samples containing boric acid were resistant, whereas those containing primarily sulfates supported fungal growth. Thermal conductivity values for two of the eight samples tested exceeded the values reported by the manufacturers; the range of deviations was 11 to 63 percent. The standard specifications ~How only a 5 percent deviation. It is interesting to note that ASTM C739-73 provides for three classes of "Cellulosic Fiber Loose Fill Thermal Insulation," i.e., Type I has a flamespread of 0-25; Type II has 2675; Type III has 76-200. To establish three classes appears to me to be the height of assininity. For three classes of readily or highly combustible material to be placed in concealed spaces where it may be subjected to accidental ignition is inexcusable! Unless something is done about it, and immediately, we are building for a rash of fire deaths in the foreseeable future. Reports on the cellulosic insulating materials have been received from as far north as Edmonton, Alberta, and from as far south as Florida. Concern has been expressed about the covering over of electrical fixture boxes. Oklahoma City placed a moratorium on the installation of recessed electrical fixtures, so tests were conducted. "Insulation was blown in to the suggested "R" value. After one hour and 45 minutes a heat rise of 650 degrees Fahrenheit was recorded, joists were charred from heat being conducted through fixture hangers and metal flex cables, wiring insulation was melted with bare wire exposed, all paint was burned off of recessed fixtures, and plastic connectors were melted in the UL-listed connector box. The only method of clearance that maintained safe temperatures was the metal enclosure over recessed incandescent fixtures." In Oregon, the cellulose insulation identified as to its fire-resistant qualities came into contact with a bathroom July 1978 RAIN Page 11 heat lamp, and fire resulted. Another Oregon community passed a local ordinance in the late '60s prohibiting the use of cellulosic insulation "due to the lack of adequate uniform fire-resistive treatment." But fires are still occurring due to the quantities installed prior to that prohibition. Phoenix reported that insulation fires generally increased 30 percent between 1975 and 1976. Michigan has reported numerous fires. So have Texas, Alabama, Colorado and other states. Reprinted from Fire Journal, National Fire Protection Association, 470 Atlantic Ave., Boston, MA 02210, May 1978. Cellulose Fiber. Cellulose fiber insulation is like expanded perlite and expanded vermiculite in that it is a loose material. It is either poured or blown into the joist or stud space. It is unlike the mineral insulating materials in that it is combustible. Cellulose fiber insulation is produced by shredding wood or paper, pulverizing it in hammer mills, then blending the material with a dry chemical to achieve some degree of fireretardance. The chemicals used for the fire-retardant treatment may be one or a mixture of the following: borax, boric acid, mono- or diammonium phosphate, and ammonium sulphate. Other fire-retardant chemicals may also be used. These chemicals are water soluble and may be adversely affected by repeated exposure to moisture or extreme changes in humidity. There is some question about whether such changes would result in migration of the chemical deeper into the fibers or lower in the bed of insulation. Insulating material treated with sulfates may cause corrosion of metal-sheathed cable or metal fixtures, especially under humid conditions. Not all cellulose fiber insulations are listed by testing laboratories. Those that are listed generally have flame spread ratings ranging from 15 to 60. Under favorable conditions, cellulose fiber insulation will smolder or glow, especially if a source of ignition penetrates deep into the bed of material. With a sizable, sustained ignition source present, the chemicals will eventually break down and the insulating material will burn.
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