Water will sheet off the part rather than bead
- Take a cleaned and dried part and set it in a vertical position.
- Use a spray bottle containing distilled water.
- Spray the part two to three times from at least 6" away.
- If the part is clean and free of oily residue, the water spray should sheet off.
- If some oily residue remains, the water will tend to bead on the part
UV Black Light:
Can you see fluorescence on the parts when viewed using a black light?
- Take the cleaned and dried part and the black light into a dark area.
- In the dark area, shine the black light onto the part.
- If the part is free of soils, it should not highlight any fluorescence
- If some soil remains, you should see some florescence where the soil is present.
- You should check a dirty part for florescence to ensure that the soil emits a florescence when viewed under a black light.
Will a white cloth remain white after being rubbed on the cleaned part?
- Take the cleaned and dried part and wipe it with a portion of a clean, white, lint-free cloth.
- If the cloth remains clean, the part is sufficiently clean.
- If the cloth becomes soiled or discolored, the part still contains soil residue.
Will tell how much contaminate is left on the part
- Involves filtering a contaminated sample through a control filter and a sample filter.
- Place two pre-weighed filters, one on top of the other in a single filter holder.
- Sample contaminants will be retained entirely by the top test filter.
- Both filters are subjected to identical alterations in tare weight as a result of moisture.
- Any change in weight of the bottom ("control") filter is then applied as a correction to the weight of contaminant.
- Results accurate to 0.1 mg are routinely attained using this method.