PlasmaQuant MS product family
Maintenance and care
107
Check the torch for cracks or deformation caused by overheating. You should replace
the torch if any part of it is cracked, partly melted, or severely eroded.
Specifically, inspect the torch for:
Deposits in the injector tube (the innermost tube of the torch, which carries the
sample), which could affect sample introduction to the plasma or interfere with
analyses.
Deposits between the intermediate and outer tubes of the torch, which may block
gas flow to the plasma, extinguishing the plasma altogether. Partial blockage in
this area can cause localized torch overheating.
Deposits on the end of the outer tube of the torch, which may cause localized torch
overheating and lead to deformation of the torch.
WARNING
Nitric acid (HNO
3
), hydrochloric acid (HCl), aqua regia and hydrofluoric acid (HF) are
all very corrosive and can cause severe burns when they come in contact with the skin.
Always wear appropriate protective clothing when handling these acids. For handling
hydrofluoric acid (HF) a face shield is needed.
NOTICE
Hydrofluoric acid is highly corrosive. Repeated or continual use of hydrofluoric acid
may cause the walls of the torch to weaken or break.
Always ensure that the torch is completely dry before replacing it in the instrument.
Any moisture remaining in the torch will cause difficulties during plasma ignition.
The cleaning requirements for the torch will vary, depending on the type of sample
matrix analyzed. It may not be necessary to complete all of the steps below when
cleaning the torch.
1.
Soak the torch in water to see if any of the deposits will dissolve in water.
2.
For more stubborn deposits and stains, soak the torch overnight in aqua regia
(concentrated nitric and hydrochloric acid 1:3 by volume).
3.
For persistent stains, soak the torch in diluted hydrofluoric acid for a few seconds.
Repeat if necessary.
4.
Once the torch is clean, rinse it well with ultrapure water and blow it dry with
argon or nitrogen.
10.3.5
Replacing peristaltic pump tubing
Check the pump tubing daily before starting work and replace any tubing if it is
discolored, no longer flexible or even porous (see the section "Installation of the
peristaltic pump tubing" p. 50).
Inspecting the torch
Cleaning the torch