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Radiation Safety

Background Information
Gamma Radiation
Health Concerns

Radiation Theory
Nature of Radiation
Sources of High Energy

Rad for Ind Radiography
Decay and Half-life
Energy, Activity, Intensity   and Exposure
Interaction with Matter
Measures Related to   Biological Effects

Biological Effects
Biological Factors
Stochastic (Delayed) Effects
  -Genetic Effects

Nonstochastic (Acute) Effects

Safe Use of Radiation
NRC & Code of Federal
Exposure Limits
Controlling Exposure
  -Time-Dose Calculation
  -Distance-Intensity Calc
HVL Shielding
Safety Controls

Survey Techniques

Radiation Safety Equipment
Radiation Detectors
Survey Meters
Pocket Dosimeter
Audible Alarm Rate Meters
Film Badges

Video Clips



Exposure Symptoms

Listed below are some of the probable prompt and delayed effects of certain doses of radiation when the doses are received by an individual within a twenty-four hour period.

Dosages are in Roentgen Equivalent Man (Rem)

• 0-25 No injury evident. First detectable blood change at 5 rem.
• 25-50 Definite blood change at 25 rem. No serious injury.
• 50-100 Some injury possible.
• 100-200 Injury and possible disability.
• 200-400 Injury and disability likely, death possible.
• 400-500 Median Lethal Dose (MLD) 50% of exposures are fatal.
• 500-1,000 Up to 100% of exposures are fatal.
• 1,000-over 100% likely fatal.

The delayed effects of radiation may be due either to a single large overexposure or continuing low-level overexposure.

Example dosages and resulting symptoms when an individual receives an exposure to the whole body within a twenty-four hour period.

100 - 200 Rem  
First Day No definite symptoms
First Week No definite symptoms

Second Week

No definite symptoms
Third Week Loss of appetite, malaise, sore throat and diarrhea
Fourth Week Recovery is likely in a few months unless complications develop because of poor health
400 - 500 Rem  
First Day Nausea, vomiting and diarrhea, usually in the first few hours
First Week Symptoms may continue
Second Week Epilation, loss off appetite
Third Week Hemorrhage, nosebleeds, inflammation of mouth and throat, diarrhea, emaciation
Fourth Week Rapid emaciation and mortality rate around 50%