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 <text x="380" y="63" font-size="24" font-weight="800" fill="#062f35">Evidence chain for a useful silica specification</text>
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  <text x="140" y="145">REFERENCE</text><text x="140" y="169" font-size="13" font-weight="500">Standard / calibrated method</text>
  <text x="380" y="145">MEASUREMENT</text><text x="380" y="169" font-size="13" font-weight="500">Measurand + uncertainty</text>
  <text x="620" y="145">LOT CERTIFICATE</text><text x="620" y="169" font-size="13" font-weight="500">Product-specific result</text>
  <text x="260" y="301">USER PROCESS</text><text x="260" y="325" font-size="13" font-weight="500">Dilute / deposit / aerosolize</text>
  <text x="500" y="301">APPLICATION</text><text x="500" y="325" font-size="13" font-weight="500">Instrument or process decision</text>
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 <text x="380" y="405" font-size="15" fill="#526d72">Each handoff adds conditions, controls and potential uncertainty.</text>
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