Waters Xevo TQD Operator's, Overview And Maintenance Manual page 128

To clean the ion block components
1. Immerse the ion block and isolation valve in separate glass vessels
containing 1:1 methanol/water.
If the components are obviously contaminated, use 45:45:10
Tip:
methanol/water/formic acid.
2. Place the vessels in the ultrasonic bath for 30 minutes.
3. If you used formic acid in the cleaning solution, do as follows:
a. Rinse the components by immersing them separately in glass
vessels containing water and then place the vessels in the ultrasonic
bath for 20 minutes.
b. Dry the components by immersing them in separate glass vessels
containing methanol and then place the vessels in the ultrasonic
bath for 10 minutes.
4. Carefully remove the components from the vessels, and blow-dry them
using inert, oil-free gas.
5. Inspect each component for persisting contamination. If contamination
is present, do as follows:
a. Use the wash bottle containing 1:1 methanol/water to rinse the
component over the large beaker.
b. Blow-dry the component with inert, oil-free gas.
4-52 Maintenance Procedures
The ion block components can be contaminated with
Warning:
biohazardous and/or toxic materials. Always wear
chemical-resistant, powder-free gloves while performing this
procedure.
Formic acid is extremely corrosive and toxic. Work with
Warning:
extreme care, use a fume hood and suitable protective
equipment.
To avoid recontaminating the components, wear clean,
Caution:
chemical-resistant, powder-free gloves for the rest of this
procedure.