PROCESS:

Use of detector dewar ion pump. All of the lab detector dewars use a high voltage ion pump to maintain vacuum for long periods of time. The primary hazard associated with these ion pumps is the high voltage supply. The high voltage supply is typically a Varian Vacion Pump Control Unit, model 921-001, which produces about 3KV to operate the ion pump.

HAZARDOUS CHEMICALS/CLASS OF HAZARDOUS CHEMICALS:

None.

PERSONAL PROTECTIVE EQUIPMENT:

None.

ENGINEERING/VENTILATION CONTROLS:

Minimize the possibility of hazardous shocks by always attaching the ground wire between the ion pump power supply and the dewar housing.
The power supply has been equipped with a current limiting circuit and a drop-out relay to prevent excessive currents from developing which could overheat and damage the power supply or the ion pump and in turn present a hazard to either the operator or the detector.

SPECIAL HANDLING PROCEDURES AND STORAGE REQUIREMENTS:
 

1. Make sure the Varian power supply is turned off before beginning work.
2. Attach the red grounding wire between the power supply and the detector dewar.
3. Attach the power supply high voltage connector to the ion pump. It is a simple push-on connector. Make sure it is seated firmly.
4. Turn on the power supply with the toggle switch on the front of the supply.
5. Place the power supply current meter control knob in the milliamp range.
6. Press and hold in the red button on the front of the power supply. This closes the drop-out relay and allows the power supply to generate high voltage. Monitor the current meter. The current should drop below 3 milliamperes quickly. When the current drops below this limit the current limiting circuit will engage the drop-out relay and the red button can be released. If the current does not drop below 3 milliamps within 30 seconds this may indicate a vacuum leak. Release the red button and the high voltage will shut off.

CALL 911 in case of electrical shock.

WASTE DISPOSAL:

None