Vacuuming - doe-std-1128-98

DOE-STD-1128-98

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 non-contaminated 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 (although the last item need not be of importance).

However, in dry glove boxes with dusty operations using high-exposure

plutonium, personnel exposure control is a problem and vacuuming is a

quick and effective method of keeping the dust and exposure rates under

control and should be considered.

Note: The use of vacuum cleaners may require review by Facility Criticality

Safety personnel because vacuum cleaners are likely to concentrate

fissionable material.

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