Leak Detector Paper offers the analyst a visual method to assess sample cup leakage. The procedure is simply based on observing the appearance of a tell-tale stain on Leak Detector Paper from a fluid-filled sample cup. Leak detection is subject to the type of sample, its effect on the paper and time duration tests that could range from almost immediately to overnight. The most likely cause of sample cup leakage may be attributed to chemical attack of a thin-film substance by the sample, inadvertent improper attachment of a thin-film to the sample cup cell and poor design and manufacturing tolerance control of the sample cup components.
Selection of the most chemically resistant thin-film substance should be the first item to evaluate and test prior to usage in the instrument. The chemical resistance of typical thin-film window substances to different types of liquid samples is illustrated in the Thin-Film Resistance to Chemical Attack Table. Chemical sample classifications are categorically grouped and specific thin-film substances. Chemical resistance is listed simply as Excellent, Good, Fair, Not recommended or Unknown.
The manipulation of attaching a thin-film window to a sample cup is another factor influential to leak formation. Initial misalignment of the sleeve with the cell may create thin-film stretching, alter the tolerance and serve as foci for leakage. Attempts to reattach create unwanted wrinkles and are frequently futile.
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