About This Manual
Using Hydrogen
xviii
Maintenance and Troubleshooting Manual
Use the following safety precautions when using hydrogen:
•
Ensure that all hydrogen cylinders comply with the safety requirements for
proper use and storage. Hydrogen cylinders and delivery systems must
comply with local regulations.
•
Make sure the gas supply is turned completely off when connecting hydrogen
lines.
•
Perform a bubble test to ensure that the hydrogen lines are leak-tight before
using the instrument. Perform the bubble test after performing the pressure
test described in the
Performing a Manual System Leak Check
operating
procedure on page 66 of the Operating Manual.
•
Ensure your GC column oven has a hydrogen sensor. A hydrogen sensor con-
tinuously monitors the hydrogen level in the GC column oven.
If your GC oven does not have a hydrogen sensor already installed, contact
your Thermo Fisher Scientific sales representative. To comply with
instrument safety requirements, a Thermo Fisher Scientific CSE or authorized
service technician should install the sensor
If you plan to use a sensor other than the sensor recommended by Thermo
Fisher Scientific, you must verify its ability to perform the functions listed
above before installing it. It must comply with your local safety regulations,
or with the IEC 1010
1
regulations if local regulations do not exist.
Using the Hydrogen Sensor
The lower limit of the hydrogen sensor is 0.5% in volume. You should adjust the
detection threshold to 1% in volume, which is 25% of the hydrogen lower limit of
explosion (4% in volume).
In cases where the connections begin to leak or the column breaks, the sensor
alerts the operator. Then it automatically cuts off the gas supply and heating to the
active zones, and sweeps the column oven with forced air ventilation.
1. IEC 1010-1, First Edition, September 1990; IEC 1010-1, Amendment 1, September 1992; IEC 1010-1, Amendment 2,
June 1995.