6.2 Cleaning the ADF
As a Guideline, clean the ADF every 10,000 scanned sheets. Note that this guideline varies according to the type of documents you scan. For example, it may be necessary to clean the ADF more frequently if documents are scanned when the toner is not sufficiently fixed on the printout.
When operating the scanner, the glasses inside the 
ADF become very hot.
Before you clean the inside of the scanner, turn off its power and unplug the power cable from the power outlet. Wait for at least 15 minutes for the ADF glasses to cool down.
Cleaning with a Cloth Moistened with Cleaner F1
1 Turn off the scanner, and wait for at least 15 minutes.
For how to turn off the scanner, refer to "1.4 Turning the Scanner ON and OFF" (on page 31).
Be careful, the ADF may close and pinch your
fingers.
3 Clean the following locations using a cloth moistened with Cleaner F1.
To avoid damaging the document sensors, take care so ！ the cloth does not hook them during wiping.
Document sensor
2 Pushing the ADF Open Buttons, lift open the ADF.
ADF Open Button 
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