Solution  A homogeneous substance, usually a single phase mixture of two or more materials.

Solvent  A substance which dissolves another to form a solution.

Sorbency  A collective term describing the tendency of a wiper to hold fluids, whether by absorption (within the capillaries or pores of the wiper) or by adsorption (as a surface phenomenon).

Sorbent  A liquid or solid medium in or upon which materials are retained by absorption or adsorption.

Sorption  A process consisting of either absorption or adsorption.

Standard Air  Air at 50% relative humidity 70^oF and 29.92 in. Hg (21^o and 760mm Hg).  These conditions are chosen in recognition of the data which has been accumulated on air-handling equipment.  They are sufficiently near the 25^oC and 760mm Hg commonly used for indoor air contamination work that no conversion or correction ordinarily need be applied.

Standard Air Density  Air having approximate density of .075 lb/ft³ (1.201 kg/m^3).  this corresponds to air at a pressure of 29.92 in Hg (760 mm Hg) at temperature of 69.8^oF (21^oC) with a specific volume of 13.33 ft³/lb (0.832m³/kg).

Sterile  Having no living matter present.  This would include all microbiological life, such as bacteria, fungi or viruses.

Sterile Cleanrooms  Cleanrooms supplied with microbial-free air and are positively pressurized against the admission of contaminated air from adjacent areas.

Tacky Mat  A large mat placed on the floor just outside the entrance to the Cleanroom itself.  The top surface of the mat is coated with a stick film which is designated to remove excess particles from the soles of the Cleanroom operator's footwear just prior to entry.  The sticky mat is usually in the form of a pad so that when the top mat has lost his stickiness, it is simply peeled off and thrown away, thus leaving a fresh mat in position.