8. Make sure there is no material left on the build-unit seal. Clean it with an explosion-protected
vacuum cleaner, then wipe it with a cloth dampened with deionized water. If any material is still left,
remove it with a scraper.
9. Besides vacuuming, you must clean the rear areas indicated below with a lint-free cloth dampened
with general-purpose industrial cleaner
156 Chapter 11 Hardware maintenance