Glossario

Absolute filtration rating

The diameter of the largest solid spherical particle that will pass through a filter under specified test conditions. This is an indication of the largest opening in the filter cloth.

Absorption

Retention of liquids in the bulk of the fabric where the liquid is retained by filling up void spaces, i.e. pores of the fiber, between fibers in a yarn and between yarns in the fabric.

Air flow/air permeability

Measure of the amount of air that flows through a filter – a variable of the degree of contamination, differential pressure, total porosity, and filter area. Expressed in ft3/min/ft2 or l/min/cm2 at a given pressure.

Antistatic (mesh)

Material that minimizes static charge generation, provides 'controlled' static charge dissipation, or both.

Aperture size

See Mesh Opening

Attenuation

Reduction of the signal power or field strength as a function of distance through a material. Also refers to shielding effectiveness.

Autoclave

Vessel for high steam pressure heating of materials. Used for sterilization and other applications.