Radioactive Material Exposure

DOE-HDBK-1132-99

These surprises can manifest themselves in

liquids found in a " rained"system,

explosive gases found in drained systems,

various concentrations or mixtures of the expected chemical actually

found,

crystals of evaporated chemicals rather than the liquids or vice versa, and

salt cake or sludge-oozing liquids even after significant drying or

solidification steps are undertaken.

The level of planning and control of the operation should take hazard level and

exposure scenarios into account prior to the start of work. Any planning should

always provide built-in contingency for the surprise that will occur during the

decommissioning project.

Radioactive Material Exposure . Control of radiological exposure is well-

established within any nuclear operations organization and those same

principles of ALARA should be applied to the decommissioning work. The

difference is that more unknowns should be expected, more scheduling options

may be available to remove a source term, and the opportunities to spread

contamination is greater during decontamination and piping system removal

than during facility operations. In general, control techniques such as those

listed below should be considered for decommissioning work:

Removing a high-dose contributor earlier rather than shielding is

preferred.

Inhalation issues should be controlled as close to the source as possible.

Engineering controls take precedence over protective clothing, and both

methods are better than administrative controls.

Exposure controls are needed until the waste leaves the site.

Use of the same control mechanism for chemical and radiological

exposure should be investigated and used whenever possible.

I-137