MVE TEC 3000 Guide De Référence Rapide page 5

Equipment Usage
Cryogenic containers must be operated in accordance with the manufacturer/supplier instructions. Safety
instructions will also be posted on the side of each Dewar. Cryogenic Dewars must be kept in a well-
ventilated area protected from weather and away from heat sources. In applications that use a modular
liquid cylinder as a source of LN2, the supply will need to be replenished at regular intervals to ensure
proper operation of the freezer. When exchanging liquid cylinders, follow the below procedure:
1. Allow all plumbing components to warm to room temperature before attempting to
change supplies.
2. Close all valves associated with the liquid supply cylinder.
3. Relieve pressure in the plumbing assembly by initiating a brief fill by either pressing "Start
Fill".
4. Loosen the plumbing connection for the transfer hose at the liquid cylinder.
5. Remove empty liquid cylinder and replace with full liquid cylinder pressurized to 22 - 35
psig (1.52 - 2.41 bar).
6. Attach the transfer hose to the plumbing connection on the liquid cylinder. Ensure that
the hose is connected to the connection labeled "LIQUID".
7. Tighten the transfer hose plumbing connection at the liquid cylinder.
8. Open the liquid supply valve on the liquid cylinder.
9. Inspect plumbing for audible and visual leaks. Repair if necessary.
10. Manually initiate a fill to verify proper operation.
Recommended First Aid
Every site that stores and uses LN2 should have an appropriate Material Safety Data Sheet (MSDS)
present. The MSDS may be obtained from the manufacturer/distributor. The MSDS will specify the
symptoms of overexposure and first aid to be used. Here is a typical summary.

If symptoms of asphyxia such as headache, drowsiness, dizziness, excitation, excess
salivation, vomiting, or unconsciousness are observed, remove to fresh air. If breathing
has stopped, give artificial respiration. CALL A PHSYICIAN IMMEDIATELY. If
breathing is difficult, supplemental oxygen maybe required.

If exposure to cryogenic liquids or cold vapor occurs, restore tissue to normal, body
temperature (37°C) as rapidly as possible, and then protect the injured tissue from further
damage and infection. Rapid warming of the affected areas is best achieved by bathing it
in warm water. The temperature of the water used should not exceed 40°C. Under no
circumstances should the frozen part be rubbed either before or after warming. If the
eyes are involved, flush them thoroughly with warm water for at least 15 minutes. In case
of massive exposure, remove clothing while showering with warm water. The patient
should not drink alcohol or smoke. CALL A PHYSICIAN IMMEDIATELY.
TEC 3000 Quick Reference User Manual