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IMPACT ON RADIOLOGICAL BARRIERS AND CONTROLS AT FACILITIES
Radiological barriers and controls

WORKED EXAMPLE: SPILLAGE OF PLUTONIUM CONTAMINATED LIQUID ONTO A LABORATORY FLOOR

 
Summary:
  • Water flooded a glove box and filled the glove until it burst
  • The spilled water contained about 2.3 GBq of 239Pu
  • There was no release from the site

Scenario

A flexible hose feeding cooling water to a glass condenser in a glove box became detached. Water flooded the glove box and filled the glove until it burst. The spilled water contained about 2.3 GBq of 239Pu.

INES procedure (click the highlighted flowchart items to follow the procedure)

Figure 4, page 145 of the Manual

Figure 6, page 147 of the Manual

Calculate radiological equivalence

Here's the calculation:

2.3 GBq 239Pu = 0.0023 TBq 239Pu
0.0023 x 57 000(multiplication factor for liquid contamination based on 99Mo equivalence) = 131.1 TBq 99Mo

Check the answer

Answer

There was a spillage of liquid radiologically equivalent to a spillage of the order of 131 TBq 99Mo.

Level 2 defines that there should be:
"A spillage of liquid radioactive material radiologically equivalent to a spillage of the order of 10 TBq 99Mo"

The Level 3 definition involves a few thousand terabecquerels of activity, so 131.1 TBq is well below this level.

Therefore, the spillage of plutonium contaminated liquid onto a laboratory floor would be rated at Level 2.