PerkinElmer AAnalyst 700, User Manual

Page: 26 / 194

Safety/Regulatory Information
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Acetylene

Always use ‘Atomic Absorption Grade’ acetylene (ethyne) dissolved in
acetone (propan-2-one). This is satisfactory for all PerkinElmer AA
spectrometers.

Do not store acetylene in close proximity to oxidizing gases, such as nitrous
oxide.

Use approved tubing and fittings for acetylene. Never use copper fittings
since acetylene forms an explosive compound with copper.

Prevent acetylene from coming into contact with copper, silver, mercury or
gaseous chlorine.

Periodically check for the presence of acetylene in the laboratory atmosphere,
especially near the ceiling.

For acetylene, set an outlet gauge pressure of between 90 kPa and 100 kPa
(0.9–1.0 bar, 13–14.5 psig). Never allow the outlet gauge pressure to exceed
103 kPa (1.03 bar, 15 psig); acetylene can explode spontaneously above this
pressure.

Solvent Carryover.
If the acetylene cylinder pressure falls to below 600 kPa / 6.0 bar /
87 psig (at 20 °C), some of the solvent used to stabilize the acetylene (such as
acetone) may be carried over into the burner. This could influence the
characteristics of the burner with a resulting influence on the analytical
results.
Change to a new acetylene cylinder when the cylinder pressure falls to below
this value.