26 September 2006
A sheet material produced
of fibers (or
both) by mechanical, thermal or solvent means (or combinations thereof).
Olefin. An unsaturated open-chain hydrocarbon containing at least one double bond:
ethylene or propylene.
Olefin Plastics. Plastics based on polymers made by the polymerization of olefins or
copolymerization of olefins with other monomers, the olefins being at least 50 percent of
Organic (adj.). Composed of hydrocarbons or their derivatives; or matter of plant or
Organic coating. Coatings that are generally inert or inhibited. May be temporary (e.g.,
slushing oils) or permanent (paints, varnishes , enamels, etc.).
Organic content. Usually synonymous with volatile solids in an ashing test; e.g., a
discrepancy between volatile solids and organic content can be caused by small traces
of some inorganic materials , such as calcium carbonate, that lose weight at
temperatures used in determining volatile solids.
Panel clip. Independent clip used to attach roof panels to substructure.
Panel Creep. Tendency
of the transverse dimension
of a roof panel
modularity due to spring-out or storage-distortion.
Parapet. Portion of wall above the roof line.
Pea Gravel. Small gravel with a diameter approaching that of a pea. Size roughly
defined by ASTM D448-03 Standard Classification for Sizes of Aggregate for Road and
Bridge Construction, Number 7 or smaller.
Peak. The uppermost point of a gable.
Penetration. The consistency of a bituminous material expressed as the distance in
tenths of a millimeter (0.1 mm) that a standard needle or cone vertically penetrates a
sample of material under specified conditions of loading, time, and temperature.
Percent Elongation. In tensile testing, the increase in the gauge length, measured
after fracture of the specimen within the gauge length.
Perlite. An aggregate used in lightweight insulating concrete and in preformed perlite
insulating board, formed by heating and expanding siliceous volcanic glass.
Permeability. (1) The capacity of a porous medium to conduct or transmit fluids; (2)
The amount of liquid moving through a barrier in a unit time, unit area and unit pressure
gradient not normalized for but directly related to thickness; (3) The product of vapor
permeance and thickness (for thin films, ASTM E96-00e1 Standard Test Methods for
Water Vapor Transmission of Materials--over 3.2 mm (.125 in.), ASTM C355 Usually