Staff Education | People's Choice Urgent Care of Delaware County

Module 1

Radiation Physics & X-Ray Production

Fundamental principles of electromagnetic energy, x-ray tube components, interaction mechanisms, and beam quality.

The X-Ray Tube Assembly

Cathode (-): Contains filament (tungsten wire) and focusing cup (nickel). Emits electrons via thermionic emission when heated.
Anode (+): Target made of tungsten-rhenium alloy (high melting point: 3410°C, atomic number Z=74). Rotates at 3,400 to 10,000 RPM to dissipate heat.
Line Focus Principle: By angling the anode target (typically 7°–17°), the effective focal spot is smaller than the actual focal spot, improving spatial resolution while maintaining heat distribution capacity.
Anode Heel Effect: Radiation intensity is higher on the cathode side of the tube due to photon absorption in the anode target heel. Clinical rule: Place thicker body parts under cathode end!

X-Ray Production Interactions

Bremsstrahlung Radiation ("Braking"): Accounts for ~85% of primary diagnostic beam. Incident electron is slowed/deflected by nucleus of tungsten atom, releasing energy as an x-ray photon. Polyenergetic spectrum.
Characteristic Radiation: Accounts for ~15% of beam (only occurs at > 69.5 kVp with tungsten). Incident electron ejects an inner K-shell electron; outer shell electron drops to fill vacancy, emitting a discrete energy photon (69.5 keV).
Half-Value Layer (HVL): The thickness of absorbing material (usually Aluminum) needed to reduce total x-ray beam intensity by 50%. Measures beam quality/hardness.

Module 2

Radiation Protection & Biological Effects

ALARA compliance, dose limits, radiobiology principles, and patient shielding protocols.

ALARA & Dose Limits

3 Cardinal Rules: Time (minimize beam time), Distance (maximize distance - Inverse Square Law), Shielding (lead aprons, thyroid shields).
Occupational Annual Limit: 50 mSv (5 rem) total effective dose equivalent per year.
Cumulative Lifetime Limit: 10 mSv × age in years (e.g., 30 yrs old = 300 mSv max).
Embryo/Fetus Dose (Declared Pregnancy): 0.5 mSv (0.05 rem) per month; total 5.0 mSv for entire pregnancy.
Public Annual Limit: 1 mSv (0.1 rem) per year for continuous exposure.

Radiobiology & Cellular Sensitivity

Law of Bergonié & Tribondeau: Radiosensitivity of cells is directly proportional to their reproductive activity and inversely proportional to their degree of differentiation. Highly sensitive: Stem cells, lymphocytes, erythroblasts. Resistant: Muscle & nerve cells.
Deterministic (Tissue) Effects: Have a threshold dose. Severity increases with dose (e.g., skin erythema, cataracts, epilation).
Stochastic (Probabilistic) Effects: No threshold dose. Probability increases with dose, but severity does not (e.g., cancer induction, genetic mutations).

Module 3

Image Formation, Equipment & Exposure Factors

Understanding kVp, mAs, grid performance, collimation, and spatial resolution.

Primary Exposure Factors

kVp (Kilovoltage Peak): Controls energy/penetrating power of beam. Determines image contrast. High kVp = low contrast (long scale, lots of grays).
mAs (Milliampere-seconds): Product of tube current (mA) and exposure time (seconds). Controls total photon volume/receptor exposure.
15% Rule: Increasing kVp by 15% doubles image receptor exposure (equivalent to doubling mAs). To maintain density while reducing dose: Increase kVp by 15% and cut mAs in half.

Grids & Scatter Control

Grid Usage Rule: Indicated for body parts measuring > 10 cm thick or when using > 60-70 kVp.
Grid Ratios & Conversion Factors (GCF):
• No Grid = 1 GCF
• 5:1 Grid = 2 GCF
• 8:1 Grid = 4 GCF
• 12:1 Grid = 5 GCF
• 16:1 Grid = 6 GCF
Grid Cutoff: Undesirable absorption of primary beam causing reduced exposure on edge or entire image (Off-level, Off-center, Off-focus, Upside-down grid).

Module 4

Anatomical Positioning & Procedures

Positioning criteria for chest, upper/lower extremities, and spine.

Chest & Ribs

PA Chest: 72" SID, CR perpendicular to T7 (inferior angle of scapula). Full inspiration (10 posterior ribs demonstrated).

Lateral Chest: Left lateral preferred to reduce cardiac magnification. Arms elevated above head.

Upper Extremities

Hand/Wrist: 40" SID. AP, Oblique (45°), Lateral. CR to 3rd MCP joint for hand; mid-carpal area for wrist.

Forearm/Elbow: Include both wrist and elbow joint. Epicondyles parallel to IR for AP elbow.

Lower Extremities & Spine

Foot/Ankle: AP Foot CR angled 10° posteriorly to base of 3rd metatarsal. AP Ankle CR perpendicular midway between malleoli.

Lumbar Spine: AP CR to iliac crest (L4-L5). Lateral CR to crest or L3. High mAs required.

Module 5

Patient Care, Safety & Urgent Care Operations

Patient identification protocols, infection control, HIPAA, and urgent care safety.

Patient Identification & Safety

Two Identifiers: Always verify patient identity using at least 2 unique identifiers (Full Name & Date of Birth) before procedure.
Pregnancy Screening: Mandatory screening for females of childbearing age (12–55 years) prior to exposure. Ask date of last menstrual period (LMP).
HIPAA Compliance: Protect all PHI (Protected Health Information). Log out of imaging workstations when stepping away.

Infection Control & Urgent Care Management

Standard Precautions: Treat all blood and body fluids as potentially infectious. Hand hygiene before and after patient contact.
Disinfection: Clean image receptors (cassettes), positioning sponges, and x-ray table with approved disinfectant wipes after every patient scan.
Emergency Management: Know location of emergency crash cart, oxygen supply, and AED in urgent care clinic.

RAD-PREP PRO

Limited Scope Radiography Prep

Core Module Readiness Checklist

Radiation Physics & X-Ray Production

The X-Ray Tube Assembly

X-Ray Production Interactions

Radiation Protection & Biological Effects

ALARA & Dose Limits

Radiobiology & Cellular Sensitivity

Image Formation, Equipment & Exposure Factors

Primary Exposure Factors

Grids & Scatter Control

Anatomical Positioning & Procedures

Chest & Ribs

Upper Extremities

Lower Extremities & Spine

Patient Care, Safety & Urgent Care Operations

Patient Identification & Safety

Infection Control & Urgent Care Management

Interactive High-Yield Flashcard Deck

Radiographic Physics & Technical Factor Calculators

ARRT Limited Scope Practice Examination

Limited Scope Radiography Prep

Core Module Readiness Checklist

Radiation Physics & X-Ray Production

The X-Ray Tube Assembly

X-Ray Production Interactions

Radiation Protection & Biological Effects

ALARA & Dose Limits

Radiobiology & Cellular Sensitivity

Image Formation, Equipment & Exposure Factors

Primary Exposure Factors

Grids & Scatter Control

Anatomical Positioning & Procedures

Chest & Ribs

Upper Extremities

Lower Extremities & Spine

Patient Care, Safety & Urgent Care Operations

Patient Identification & Safety

Infection Control & Urgent Care Management

Interactive High-Yield Flashcard Deck

Radiographic Physics & Technical Factor Calculators

ARRT Limited Scope Practice Examination

Staff Account Sync