(b) The preconditioned specimens are immersed entirely
into uniform contaminated suspension. It will be lifted
gently from the solution after half a minute. And the
contamination on the steel pin and cap of specimen are
both wiped off with cotton wool, when there is no dropping
contamination suspension from the umbrella skirt edge of
polluted specimen. The specimens were suspended on the
samples shelf.
(3) Spraying Method (SM): In order to make comparisons
easier among various polluting methods, the authors added
remnant contaminated suspension from DM into a spray
connected into air compressor. The samples are preferably
mounted horizontally and slowly rotated while the
contaminating suspension is applied, resulting in a
homogeneous pollution layer.