NRSB RRS flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

ALARA principle

As Low As Reasonably Achievable; radiation protection principle to minimize dose using time, distance, and shielding.

Annual occupational dose limit

Effective dose limit for radiation workers is 50 mSv (5 rem) per year; cumulative limit is 10 mSv × age.

Inverse square law

Radiation intensity is inversely proportional to the square of distance from the source; doubling distance reduces dose to one-fourth.

Lead apron minimum thickness

Minimum 0.25 mm lead equivalent for general radiography; 0.5 mm for fluoroscopy and high-dose procedures.

Fetal dose limit

For declared pregnant radiation worker, fetal dose limit is 0.5 mSv per month and 5 mSv total gestation.

mAs effect on image

mAs controls quantity of X-rays, affecting density/brightness; doubling mAs doubles density but also doubles dose.

kVp effect on image

kVp controls quality (penetration) and contrast; higher kVp increases penetration, lowers contrast, and reduces dose.

15% rule

To maintain image density, increase kVp by 15% and halve mAs, or decrease kVp by 15% and double mAs.

Heel effect

X-ray intensity is lower on the anode side of the beam; place thicker body part toward cathode for uniform exposure.

Grid ratio

Ratio of grid height to interspace width; higher ratio (e.g., 16:1) removes more scatter but requires higher mAs.

AEC ionization chambers

Automatic exposure control uses chambers to measure radiation reaching image receptor; terminates exposure at preset dose.

Spatial resolution

Ability to distinguish small objects; determined by pixel size, focal spot, and motion; measured in line pairs per mm.

Patient identification

Use at least two identifiers (name, date of birth, MRN) before procedure; verify order and pregnancy status.

Normal adult vital signs

BP <120/80 mmHg, HR 60-100 bpm, RR 12-20/min, Temp 36.5-37.5°C, SpO2 ≥95%.

Anaphylactoid reaction treatment

Severe reaction (hypotension, laryngeal edema) requires epinephrine, oxygen, IV fluids, and emergency call.

Extravasation management

Stop injection, elevate limb, apply cold compress, document, and monitor for compartment syndrome.

Standard precautions

Hand hygiene, gloves, gown, mask, and eye protection for all patients to prevent infection transmission.

Chest PA positioning

Upright, 72-inch SID, arms out of lung fields, breath in; evaluate 10 posterior ribs and symmetric clavicles.

Abdomen AP supine

40-inch SID, include symphysis pubis to diaphragm; for obstruction use upright or decubitus views.

C-spine lateral

72-inch SID, shoulders down, visualize C1-C7; open mouth odontoid view for C1-C2.

Lumbar spine landmarks

L4 at iliac crest; L5 at posterior superior iliac spine (PSIS); T7 at inferior scapula.

Barium sulfate use

Contrast agent for GI studies; contraindicated if perforation suspected; use water-soluble iodinated contrast instead.

Exposure index (EI)

Digital metric indicating radiation reaching detector; compare to manufacturer range; deviation index = 10 log(EI/EI_target).

Reject analysis

Track reasons for rejected images (positioning, exposure, motion, artifacts); aim for reject rate below 5%.

Collimation accuracy

Light field must align with radiation field within 2% of SID; check with markers; reduces dose and improves contrast.

Monitor calibration

Use SMPTE or TG-18 pattern; luminance 350-500 cd/m2; low ambient light; clean screens regularly.

Grid artifact

Grid lines or cutoff from misalignment, wrong grid ratio, or improper distance; ensure grid centered and focused.

Scope of practice

Radiographer performs imaging under radiologist supervision; cannot interpret images or prescribe treatment.

Informed consent

Patient must understand procedure, risks, benefits, and alternatives; document consent before contrast or invasive procedures.

HIPAA confidentiality

Protect patient health information (PHI); use minimum necessary standard; report breaches per policy.

ARRT continuing education

24 credits per biennium, including at least 12 in radiography; maintain certification and ethics standards.

Malpractice elements

Negligence requires duty, breach of duty, causation, and damages; respondeat superior holds employer liable.