Hardware manual

Maintenance 4
Agilent 7500 Series ICP-MS Hardware Manual 4-41
If the signal is unstable, clean the nebulizer in the following way:
1 Disconnect the nebulizer from the end cap. Remove the O- rings.
Refer to the “Disconnecting the Concentric Nebulizer and the End Cap”
Remove both the sample tube and the connector as well.
2 Soak the nebulizer in 5% Nitric Acid both overnight.
Wear safety glasses and gloves when working with acid.
3 Check the O- rings.
Check the O- rings on the sample and carrier gas connectors and replace
them if they are cracked or too loose to seal properly. Wash the O- rings by
immersing them in pure water and dry them gently with a clean laboratory
tissue. Replace any damaged O- rings.
If necessary, also replace the end cap O- rings, which are located inside the
nebulizer end cap, and the ferrules, which are located in the connector
between the nebulizer and carrier gas tube.
4 Rinse the nebulizer in pure water at least 3 times. After rinsing, dry on a
clean surface.
5 When there is a leak, the peak count of 14, 28, 54amu will be
extraordinarily high due to nitrogen (N). Re- check the connector
connections.
NOTE
An ultrasonic wash must not be used to clean the concentric nebulizer.
If the gas tubing and sample introduction around the nebulizer leak even a small amount, it
causes a sharp signal fluctuation. To prevent leaks, be especially careful not to damage the
O-ring.