We guarantee part cleanliness through a verification process composed of any combination of the following three steps:

  • visual cleanliness verification
  • particulate verification
  • non-volatile residue (NVR) analysis and verification.

Visual verification is performed under specified lighting, magnification, and distance to ensure parts meet the specified cleanliness requirements. Depending on customer requirements, visual verification may be performed prior to particulate verification and/or prior to bagging.

The particulate count and NVR verification process begins with a pressure flush of purified, filtered verification solvent. Flushing is then repeated, this time capturing the effluent for particle count and non-volatile residue analysis.

For NVR verification, if indicated, the captured effluent is subjected to U.S Clean Lab’s proprietary NVR analysis method:

  • suitable for small quantities and sizes of hardware
  • requires less than 20 minutes to perform
  • uses less than 1 mL of solvent

For particulate verification, the captured effluent is utilized to perform particle count under ISO 14644-1 Class 4 laminar flow cabinets:

  • effluent is passed through a 0.45 micron filter by vacuum filtration
  • filter is examined under magnification
  • particle count is performed

Please contact us to learn more about cleanliness verification at U.S. Clean Lab.

Cleanliness Verification