Vacuuming - STD-1128-98master0105

DOE-STD-1128-98

Guide of Good Practices for Occupational Radiological Protection in Plutonium Facilities

boxes should be minimized. When explosive, flammable, or volatile liquids are

allowed, they should be rigidly controlled and used only in inert gas atmospheres

unless a safety analysis review shows it is safe to do otherwise. All residues should

be removed immediately at the conclusion of each job or cleaning operation.

Considerable effort has been expended on the development of coated and

corrosion-resistant tools. Some efforts have been marginally successful, but in

most cases throw-away tools are favored. Electropolishing of contaminated metal

tools and equipment has been shown to be a good method of decontamination and

allows for their reuse in some cases or disposal as noncontaminated waste. Where

possible, all tools with sharp edges or points (e.g., screwdrivers, ice picks, scissors)

should be kept out of glove boxes.

Management should constantly demand good housekeeping. Mandatory, routine

clean-up periods are becoming more common due to the increasing cost of storing

and disposing of contaminated materials. Better housekeeping is required due to

real-time, computerized accountability for nuclear materials. It has been

demonstrated that kilogram quantities of plutonium oxide dust can accumulate in

glove boxes unless they are routinely cleaned. Much of the exposure to workers

originates from layers of plutonium oxide dust on the surface of gloves and the

internal surfaces of glove boxes. In processes where plutonium oxide powder is

handled, the glove boxes should be cleaned weekly to reduce the accumulation of

dust layers and to reduce worker exposure. Although difficult to achieve and

maintain, good housekeeping is equally essential during decommissioning of

plutonium facilities.

4.2.1.2 Vacuuming

The subject of vacuuming within a glove box is somewhat complex. Experience

has shown vacuuming to be the most effective and quickest way to clean a

controlled-atmosphere (dry) glove box. It is not particularly effective for

high-humidity or wet-process glove boxes, particularly those that involve acids.

After acids have been used in a glove box, washing and wiping is the preferred

method of cleaning the etched surfaces.

Vacuuming is particularly effective in dry-atmosphere and inerted enclosures

where the levels of radioactive dust can quickly increase personnel exposure. In

many cases, vacuuming reduces the exposure level more than a wipe down with a

damp cloth, and it can be done more quickly and with less waste material

generated. Two factors weigh against vacuuming: possible safety hazards from

electrical sparks, and the occasional difficulty of operating in inert atmospheres

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