PerkinElmer AAnalyst 700, User Manual

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Laboratory Requirements
0993-5255
6 -13
Nitrous oxide supply
The nitrous oxide supply should be at least 99% pure. A heated regulator is
recommended.
Cylinder Specifications: Cylinders of nitrous oxide (99.0% minimum purity) are
available from local suppliers.
Nitrous oxide is supplied in the liquid state, initially at a pressure of about
5000 kPa (750 psig). A size 1A cylinder of nitrous oxide contains about
14800 liters (520 cubic feet) and will typically last for 10–12 hours of burning
time.
Heated Regulator: Since the nitrous oxide is in liquid form, the pressure gauge
does not give a true indication of how much nitrous oxide remains in the cylinder
until the pressure starts to fall rapidly as the residual gas is drawn off. When
nitrous oxide is rapidly removed from the cylinder, the expanding gas causes
cooling of the cylinder pressure regulator and the regulator diaphragm can freeze.
This can create erratic flame conditions or, in the most extreme case, a flashback.
It is therefore advisable to use a regulator with a built-in heater. A heated nitrous
oxide pressure regulator is available from PerkinElmer.
Warning: Nitrous oxide is a strong oxidant and an asphyxiant
Nitrous oxide is an asphyxiant; it can be considered a potential hazard whenever
it is stored or used in a confined space.
Spontaneous combustion may occur if nitrous oxide comes into contact with
grease, oil, or other organic material.

Store nitrous oxide cylinders in a well-ventilated area outside the laboratory.

Do not store nitrous oxide cylinders in close proximity to flammable gases
(e.g., acetylene).

Make sure tubing and fittings carrying nitrous oxide are free of grease, oil, or
other organic material.