scope:

Purpose

This test method establishes a procedure for determining the amount of surface ionic soil on a printed board or printed board assembly. The soil must be soluble in water, alcohol or some mixture of both. The determination can be made on either a quantitative or a qualitative basis.

Restrictions

The equipment used does not differentiate between specific ionic specie. It determines their presence and ranks them according to their ionic mobilities. Salts with higher ionic mobilities are weighed heavier than salts with lower ionic mobilities.

Application

This method has application as a quality control tool and as a method for developing and evaluating cleaning process parameters. As a quality control tool, it can be used to inspect parts to determine if they conform to pre- determined levels of cleanliness. In procecc development this procedure can be used to evaluate solvent and process efficiency and also to set levels of acceptable cleanliness.