Radiation Protection

 

Radiation Protection and Safety measures

Radiation Safety

Radiation we are discussing here are high frequency electromagnetic radiations.

Examples of Electromagnetic radiations are: Light, heat, Radio waves, Infrared, ultraviolet, Xray & Gamma Rays, though light . X ray both are electromagnetic radiations. X ray is considered hazardous, as it is of very high frequency.

  • Radiation workers in India is protected AERB (Atomic Energy Regulatory Board)
  •  The mission of the AERB is to ensure the use of ionizing radiation and nuclear energy in India does not cause undue risk to the health of people and the environment.
  •  Under AERB -RSD (Radiological Safety divisions) governs the safety requirements of radiation workers.

radiation safety

Activities of AERB

  • Frames regulations  and   amends  rules
  • Directs BARC(BABA ATOMIC RESEARCH CENTRE)to implement the regulations
  • Publication of codes and standards

Nuclear Regulatory Commission (NRC) in US

International Commission on Radiological Protection (ICRP)

Units of Radiation dose measurement

  • The Roentgen is a unit which expresses radiation protection exposure and is based on the “ionising” effect of radiation.
  • “Ionisation” creates an ion pair which consists of positively charged particle and negatively charged particle.
  • The number of ion pairs can be measured by the amount of electric current they produce, the electric current can in turn activate a survey meter.

Units of DOSE rate:

RAD- Radiation Absorption Dose

RBE- Radiation Biological Effect

REM- Radiation Equivalent Men

  • RAD- Radiation absorption Dose
  • Grey – Gy

Radiation absorbed by a nonliving cell

                                                100 rad = 1 Gy

Equivalent Dose

Radiation absorbed by a living cell

  • REM – Roentgen Equivalent Men
  • Sievert – Sv

                100 rem= 1 Sv

Regulatory Limits for Occupational Exposure

protection from radiation

  • Body cells which are active in dividing and reproducing are most vulnerable to radiation damage
  • For Persons under 18 year old the limits are only 10% (0.5 REMS) of the given value
  • Females of child bearing age are allowed to receive less mR than the radiation workers,
  • For Pregnant women – not more than 0.5 REMS for the total gestation period.
  • For a non radiation worker/Public – 0.1 REMS/year.

Effect of whole body dosage within 24 hour period

Whole body doseEffects
0 to 25 REMSNo detectable Effect
25 to 50 REMSSlight Temporary Blood Changes
100 REMSNausea, Fatigue
200 to 250 REMSFirst Death
500 REMSHalf Die (median lethal dose)

RESPECT  BUT DO  NOT  FEAR  RADIATION

radiation protector

Radiation Detection and Measurement devices

  • Survey meters
  • Direct Read Pocket Dosimeter
  • Digital Electronic Dosimeter
  • Audible Alarm Rate Meter
  • Film Batches
  • Thermoluminescent Dosimeter
  • Lead Aprons
  • Lead Suit

Principles of radiation safety

To learn more on NDT training, NDT courses and Training Institute for specific ndt methods, feel free to contact us at https://aqcinspection.com/training/ and for services on radiography testing services and other NDT services and Mechanical testing services contact us.

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