Hazy or milky glass

On the front glass, the colour and transparency change, either evenly or in patches, and the surface looks hazy or milky. It can also feel rougher than glass that has not degraded. This appearance usually points to glass corrosion or abrasion. Corrosion comes from humidity combined with pollutants, salt or ammonia. Abrasion comes mainly from wind-blown sand in deserts or from cleaning methods and agents that are too harsh. Front delamination can also look like bright, milky areas, so it is not the same thing. It is a separation between the glass and encapsulant, or between the cell and encapsulant, and it often shows bubbles, either as one continuous area or in spots. Corrosion or abrasion lowers how much light the glass lets through. The power loss is usually only a few percent and levels off over time, but losses can be larger if the glass now soils much more easily. Watch for modules that get dirty faster than usual, because that often comes with degraded glass. If you suspect the anti-reflective coating has worn off, measure reflectance with a hand-held spectrometer. A rise in reflectance after cleaning means the coating is being removed. Check the site's cleaning methods and agents first, because the wrong ones can damage or remove the coatings.

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• sentence 5: support check: partial - Passages say increased soiling susceptibility could be observed with degraded glass, but not that one should watch for it or that it 'often' accompanies degradation.
• sentence 6: support check: partial - Passages support hand-held spectrometer field measurement and reflectance rise indicating ARC removal, but the diagnostic procedure advice is inferred and the rise is in test cleaning cycles rather than a single after-cleaning check.
• sentence 7: support check: partial - Passages say inappropriate cleaning techniques and agents damage coatings, but 'check first' prioritization is not stated. -->