Instruction manual

VHS-4, VHS-6 and VHS-250 Diffusion Pumps

Dangerous Substances

Chemical Dangers of Acetone and Alcohol

Diffusion pumps are typically cleaned with acetone or alcohol. Acetone, alcohol, and most

other solvents are irritants, narcotics, and depressants, and/or carcinogenic. Their inhalation

and ingestion may produce serious effects. Even absorption through the skin can result in

moderate toxicity.

Ensure that cleaning operations are always performed in large, well-ventilated rooms. The

use of a self-contained breathing apparatus may be necessary depending upon the solvent

type and vapor concentration in surrounding air.

Poisonous and Corrosive Compounds

When pumping poisonous, reactive, and/or corrosive gas, vapors, or chemicals, proper

operation and regeneration do not always ensure that all hazardous materials have been

totally removed.

If hazardous gas, vapors, chemicals, or combustible mixtures are pumped, sufficient

quantities may exist during operation or remain after regeneration to cause severe injury or

death.

Pump Fluids

Overheating the pump fluid, exposing it to air or reactive materials, or overpressurizing it

above the normal operating range (approximately 1 x 10

−3

Torr / 1.3 x 10

−3

mbar)

decomposes the fluid and possibly makes it toxic. This is especially true of backstreamed

mechanical pump oils which are more volatile (unstable). Overheating of accidentally

introduced or backstreamed mechanical pump oils cannot be protected against by thermal

switches which are set for diffusion pump oil.

Process Gasses

These gasses are frequently toxic, flammable, corrosive, explosive, or otherwise reactive.

Agilent has no control over the types of gasses passing through your diffusion pump as these

are entirely under the control of the process user and/or the hardware systems integrator.

Since these gasses can cause serious injury or death, it is very important to plumb the

exhaust of the pump to the facility’s hazardous gas exhaust system which incorporates

appropriate filters, scrubbers and similar components to ensure that the exhaust meets all air

and water pollution control regulations.