Do not press in the condenser lens unit without the condenser lens
or without the O-ring (1A P34).
It may break the vacuum inside the spectrometer and contaminated
water in the spark stand or bubbler may enter the spectrometer. As a
result, the optical units may be contaminated, causing permanent
damage to the instrument.
12 Connect the vinyl hose for exhausting argon gas for the spark stand to the stand
following step 9 described in "5.3 Maintaining the spark stand".