Resting Rock Consulting


Project maintained by misayasu Hosted on GitHub Pages — Theme by mattgraham

Return to main

Blog 4 (12/06/2021): The Horror of Units

Radiation is a tough topic to discuss and explain. In the book “Three Mile Island,” the author J. Samuel Walker depicted the challenges that nuclear engineers and experts faced explaining radiation hazards to the public, the media, and government officials. One of the reasons was the radioactivity units.

When we try to understand scientific data, one thing that frustrates us is the units of measurement. While units might be just irritants in school exams, understanding units is a serious matter for radioactive contamination. How can we assess a situation when there are multiple definitions for ‘radiation’–exposure, absorption, inhalation, ingestion, touching, and we are unsure which definition the expert is discussing? After how long and how often does the radiation become ‘dangerous’?

Each industry and country has specific rules to express radioactivity. The United States’ love for non-SI units doesn’t help this confusing situation.

Here are some of the conversion examples between the numbers related to the Fukushima Daiichi Nuclear Power Plant accident and the radiation regulations in the U.S.

radchart
FDNPP: Fukushima Daiichi Nuclear Power Plant
Sv: Sievart
R: Rentogen
Bq: Becquerel
Ci: Curie

Nowadays, we can convert these numbers using online calculators and computer programs (although still painful). But those simple conversions do not help much when we are worried about whether any adverse health effects might occur ten, twenty, thirty years later because of the radioactivity.

So, what can we do to make these radioactivity readings more understandable for the public? There are a couple of options.

1) Use categorical descriptions for radiation hazards with timelines. Maybe we can use a coding system like METAR (METeorological Aerodrome Reports).

2) Use scales

3) Add personal situations. “&” compounds the situations.

This complexity of information is not only about units in the nuclear field. The nuclear industry has accumulated considerable data from nuclear research, nuclear incidents, and accidents in the last half-century. But a comprehensive and standardized system of defining, storing, relating, comparing, and analyzing the accumulated data is surprisingly scarce. If those systems exist, they are partial or private databases hidden from the public. If you have tried to collect information about a nuclear incident, radiation hazards, or radiation regulations, you know it is difficult to locate the information you want to obtain.

Nuclear energy is re-recognized as an energy source that emits less CO2. However, if we are to foster reasonable debates about nuclear energy, not emotional discussions, it is critically necessary to standardize nuclear-related data and present them to the public in an easier-to-understand format.

References:
US FEMA training materials
PAG Manual: Protective Action Guides and Planning Guidance for Radiological Incidents by USEPA
Protective Action Guides and Planning Guidance for Radiological Incidents (FINAL REVISION: SUPERSEDES 1992, 2013 AND 2016 MANUALS) by USEPA
https://www.iaea.org/resources/databases/itdb
https://eess.iaea.org/login.php
https://www.nrc.gov/docs/ML1028/ML102800121.pdf
https://www.nrc.gov/reactors/operating/ops-experience/tritium/public-meetings.html
https://www.osha.gov/emergency-preparedness/radiation/response
https://www.fda.gov/food/chemical-contaminants-food/supporting-document-guidance-levels-radionuclides-domestic-and-imported-foods#guides
https://www8.cao.go.jp/genshiryoku_bousai/pdf/05_shiryou0301.pdf
https://www.tepco.co.jp/decommission/progress/watertreatment/
https://nagaitakashi.net/blog/criteria/tritium/
https://www.mhlw.go.jp/shinsai_jouhou/dl/20130417-1.pdf
Personal Twitter posts (at msrmz)