Table 5.3. In Vivo Lung Measurement Bioassay Goals(a) for 241Am as an Indicator

DOE-STD-1128-98

Guide of Good Practices for Occupational Radiological Protection in Plutonium Facilities

Table 5.3. In Vivo Lung Measurement Bioassay Goals(a) for 241Am as an Indicator of Aged Weapons-

Grade Plutonium(b)

Class W Inhalation

Class Y Inhalation

Dose Limit

100-mrem

Dose Limit

100-mrem

Goal,(c)

CEDE Goal,(d)

Goal,(e)

CEDE Goal,(f)

Days Post-

nCi 241Am

Intake

7.2E-02

2.9E-03

1.8E-01

4.1E-03

6.1E-02

2.5E-03

1.6E-01

3.5E-03

4.7E-02

1.9E-03

1.3E-01

2.9E-03

4.3E-02

1.7E-03

1.3E-01

2.9E-03

3.5E-02

1.4E-03

1.3E-01

2.8E-03

2.4E-02

9.7E-04

1.2E-01

2.7E-03

1.6E-02

6.6E-04

1.2E-01

2.6E-03

180

5.1E-03

2.1E-04

1.1E-01

2.4E-03

365

4.6E-04

1.9E-05

8.9E-02

2.0E-03

730

3.8E-06

1.5E-07

6.3E-02

1.4E-03

1825

1.3E-11

5.1E-13

2.5E-02

5.6E-03

3650

6.9E-13

2.7E-14

8.2E-03

1.8E-04

7300

4.6E-14

1.8E-15

3.5E-03

7.8E-05

18250

5.0E-18

2.0E-19

3.0E-03

6.7E-05

(a)

Calculated using the CINDY Code (Version 1.3) (Strenge et al., 1992).

Defined as a Pu mixture consisting of, by weight %, 93% 239Pu, 6.1% 240Pu, 0.8% 241Pu, 0.05% 238Pu, and 0.05% 242Pu,

(b)

with 5 years allowed for 241Am ingrowth.

Intake of 4.7-nCi Pu-", 38-nCi 241Pu, and 0.34-nCi 241Am, giving a committed dose equivalent of 50 rem to the bone

(c)

surfaces.

Intake of 0.19-nCi Pu-", 1.5-nCi 241Pu, and 0.014-nCi 241Am, giving a committed effective dose equivalent of 0.1 rem.

(d)

Intake of 12-nCi Pu-", 97-nCi 241Pu, and 0.86-nCi 241Am, giving a committed dose equivalent of 50 rem to the bone

(e)

surfaces.

Intake of 0.27-nCi Pu-", 2.2-nCi 241Pu, and 0.019-nCi 241Am, giving a committed effective dose equivalent of 0.1 rem.

(f)

The problem is simply that the measurement technology is not available to provide the

sensitivities required for the 100-mrem goal using routine, periodic measurements at

reasonable frequencies. Therefore, because the goal of 100-mrem CEDE cannot be met

through routine bioassay, the radiation protection organization should take the following

administrative actions:

-- ensure that adequate control measures are applied to prevent intakes

-- document the adequate control measures for auditing purposes

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