Ch.10 Dose Limit for Exposure to Ionizing Radiation

What are the 4 big organizations that are involved in radiation protection standards?

ICRP, NCRP, UNSCEAR, and NAS/NRC-BEIR

What does ICRP stand for?

International Commission on Radiological Protection

What does NCRP stand for?

National Council on Radiation Protection and Measurements

What does UNSCEAR stand for?

United Nations Scientific Committee on the Effects of Atomic Radiation

What does NAS/NRC-BEIR stand for?

National Academy of Sciences/National Research Council Committee on the Biological Effects of Ionizing Radiation

What does ICRP do?

Evaluate information on biologic effects of RAD and provide recommendations on occupational, public dose limits, and safe use of ionizing radiation.

What does the NRCP do?

Take the recommendations from ICRP and incorporate them into U.S Radiation Protection criteria

What does UNSCEAR do?

Evaluate human & environmental exposure to ionizing RAD and its effects.

What examples does UNSCEAR evaluate?

Radioactive materials, radiation-producing machines, and radiation accidents

What does the NAS/MCR-BEIR do?

Advisory group that studies the biologic effects of low-level ionizing RAD

True or False: The big 4 organizations give recommendations on what EfD and EqD limits are based on.

True

Name the 5 Regulatory Agencies

NRC, Agreement States, EPA, FDA, and OSHA

What does NRC stand for and what do they control?

Nuclear Regulatory Commission.
Controls the use, possession, production of atomic energy for national security. More involved with nuclear/radioactive materials.

Radioisotope materials are referred to as?

NARM- Naturally occurring and/or Accelerator-produced Materials

What are Agreement States?

Enforce Radiation Protection regulations through their own health departments

What branch does Agreement States use to enforce RAD protection regulations, inspections, and approvals?

RHB- Radiologic Health Branch

What is EPA and what do they do?

Environmental Protection Agency.
Enforce protection of human health and natural environment.

What is FDA and what do they do?

Food & Drug Administration
They design and manufacture of electronic products like XR machines, and conduct inspections.

What is OSHA and what do they do?

Occupational Safety and Health Administration
Safety monitoring agency- Hazardous substances, infectious agents, Ionizing RAD

The Nuclear Regulatory Commission mandates what to be established at every facility?

Radiation Safety Committee

The RSC must be guided by a ___________

Radiation Safety Officer

What does a radiation safety officer oversee?

Create the safety rules and procedures, implement the program, & Enforce the program

Radiation For Health & Safety Act of 1968 was passed to:

protect the public from unnecessary radiation exposure from electronic products like color TVs, microwaves, and x-ray machines

The Radiation Control for Health of Safety Act of 1968 created what group that controls the standards for x-ray machines?

CDRH- Center for Devices and Radiologic Health

List the 7 Standards for Diagnostic X-Rays?

PBL, permanent filtration, reproducibility, linearity, beam limitation devices, beam-on indicators, and backup timers for AEC

What is PBL

limits the x-ray beam to the size of the image receptor (IR), regardless of the IR size.

What is permanent filtration?

Removes low-energy (“soft”) x-rays that would increase patient dose without improving the image.

What is reproducibility?

When you take the exact same image with the same technique it should look the same in density, within the 5%.

What is linearity?

Same radiation output, even when mA and time are changed. mAs is mAs, even when you change ma and time settings. The mas output should be the same

What are beam limitation devices?

Required on spot films in fluoro to reduce unnecessary radiation exposure and scatter.

What are beam-on indicators?

Gives visible warning when X-ray exposure is in progress

What are backup timers for AEC?

to ensure the termination of the exposure if the automatic timer fails

What 3 things are included in the “white paper document”?

1. Promote safe use of medical imaging devices
   2. Support informed clinical decision.
   3. Increase patient awareness.

What is the % of your EfD limit that would be an “investigation Level”?

1. 1/10 level I or 3/10 level II

Hospitals can establish investigation levels called __________

Action Limits

The Consumer-Patient Radiation Health and Safety Act of 1981 established what for x-ray schools?

To become accredited and for minimum radiation protection standards to be adopted

Name 2 goals of Radiation Protection :

1. Prevent tissue reactions from happening

2. Reduce risk of stochastic effects

Early and late tissue reactions are:

Erythema (skin redness), leukopenia, and epilation

Radiation sickness can also be:

Hematopoietic syndrome, gastrointestinal syndrome, and cerebrovascular syndrome.

Late tissue reactions due to high-level radiation expsoure are:

Cataracts, fibrosis, organ atrophy, reduced fertility

Name two stochastic effects:

cancer and genetic alterations

What are the two objections of radiation protection?

1. Prevent radiation-induced reactions by keeping doses below threshold levels

   1. Limit risk of stochastic responses to conservative level.

What is the Effective Dose Limiting System?

Method designed to protect radiation workers and general public from radiation exposure.

EDL is the ______ _________ of ionizing radiation that results in risk of bodily injury and hereditary damage

Upper boundary

The most risk for radiation-induced intellectual disability occurred when the embryo-fetus was exposed _____ to ______ after conception

8-15 weeks

What is a tissue weighting factor (Wt)?

Different tissues have different levels of radiosensitivity.

What is the occupational effective dose limit annually?

50 mSv

What is the occupational cumulative effective dose limit?

10mSv x age in years

Annual EqD for lens of eye and skin/hands/feet?

150mSV

500 mSv

Ebryo and fetus EqD monthly?

0.5mSV

Embryo and fetus entire gestation EqD limit?

5.0 mSv

Negligible annual dose?

0.01 mSV

EfD limit for education and training ?

1mSv

What has an agreement state agreed to do?

Enforce regulations thru our own state public health agency/police themselves

What did the consumer health and safety act of 1981 do?

Minimum standards and accreditation for schools of radiologic technology

Define action limit?

A dose limit that would be larger than expected. One where someone, the RSO, would take action. Usually around 10% of your efd, but different for all workers. Level I is 10% level II is 3/10^th of the allowable limit

What is radiation hormesis?

 A beneficial consequence happening from chronic low levels of ionizing radiation

What body part has the highest Wt?

gonads

Cumulative effective dose limit (CumEfD) is the sum of both _______ and ________ EqDs

internal and external

Nonoccupational Exposed individuals have a annual EDL of _______ mSV for continuous or frequent exposures from artificial sources other than medical or background radiation

1 mSV