WHEN ORGANIZATION EMBRACED

UNCERTAINTY

David M. Hamby, Oregon State University

UNC Chapel HillSeptember 1984 – January 1989

Dedicated to Dr. James E. Watson, Jr

1970 UNC PhD UNC Prof 27 yrs Several teaching awards HPS President 1985-86 24 yrs on NCs Radiation

Protection Commission North Carolina Order of

the Long Leaf Pine award

More Memories

It’s Changed in 20 Years!

1989: Time to Get a Real Job!

microDOSIMETRY =environmental DOSIMETRY

Life’s Path

1989

1994

1999

A Future of Uncertainty

What stack height can we tolerate? What happens if the deterministic

assumptions change? What difference does it make? If a particular parameter varies, how is

the result impacted? Which parameter(s) control the result?

Uncertainty of:

Atm tritium dose Food consumption

parameters Sensitivity analyses Aqueous tritium dose Parameters in

aqueous models Meteorological data

summaries Environmental

dosimetry

Iodine and trituim DCFs

Gaussian model ICRP 66 inhalation

model Env movement of

137Cs Particulate

deposition in the lung

ICRP 103 tissue weighting factors

Uncertainty in decision-making

General Method

Obtain mathematical model Characterize input parameters Execute thousands of model iterations Determine sensitive parameters Evaluate uncertainty of model output

Probabilistic Dose Estimation

Near the Dose Limit?

An Alternative View

The Complimentary View

Multiple Probabilistic Analyses

Uncertainty Presentation

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7000

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Wind speed (kts) midpoint0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30

Fre

quen

cy

WHEN ORGANIZATION EMBRACED

UNCERTAINTY

A good piece of work.

Congratulations.- Jim

Jim Watson Southern

gentleman Distinguished Soft spoken No nonsense Systematic Practical Mentor Friend

“I’ve learned that people will forget what you said, people will

forgetwhat you did, but people will never forget how you made

them feel.”- Maya Angelo