Health Physics is about radiation protection and safety involving the use of multi-discipline knowledge from physics, nuclear engineering, biology and many others. The core principle of radiation protection is the minimization of exposure. The guides to achieving this could be a reduction of exposure time, reasonable distance and / or use of shielding. The acronym ALARA –
“As Low As Reasonably Achievable.” is the watch word.
As the radiation usage becomes wide spread in most countries, there is need to develop national and international safety standards. 1897, British Roentgen Society was formed, From then till date, several national and international bodies were formed to enact safety recommendations and standards. The societies include ICRP, OSHA, and others.
Public Dose Limits:
1 mSv EfD for continuous; 5 mSv for infrequent exposure
50 mSv to skin/hands/feet
0.5 mSv/month in pregnancy once declared
Negligible Individual Dose is 0.01 mSv EfD
0.1 mSv air emissions from DOE
( Sources NCRP Report 116, Public = Non radiation worker)
Recommendations for shielding: NCRP 147 deals with medical imaging facilities and NCRP 151 deals with therapeutic facilities.
Radiation protection and safety involve a lot of regulatory issues. Examples include 1. The US FDA regulates radiation production devices, 2. The USNRC regulates exposure limits for workers and public , setting–Annual worker limit as 50 mSv (about 1 mSv/week) and annual public limit as 1 mSv.
The IAEA (International Atomic Energy Agency) is an international organization that works with local ones in each country as they work to protect the workers and public from radiation damage. The video below provides a brief synopsis of its works and contributions to radiation protection and safety.