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91¶¶Ňő

Last updated

15 August 2026

pdf, 3.51 MB
pdf, 3.51 MB

Investigate the Therac-25 medical crisis with this 6-page STEM packet covering software bugs, race conditions, radiation dose math, and safety ethics.

Engage your middle and high school students with a comprehensive, hands-on deep dive into the most infamous software bug in medical history. This complete printable unit bridges computer science, medical physics, and biomedical ethics to teach Therac-25 radiation overdose causes, software race conditions, the removal of mechanical hardware interlocks, arithmetic variable overflow errors, human-computer interface (HCI) flaw patterns, and medical device safety standards.

What’s Included in this 6-Page Unit Packet:

Page 1: Historical Case Study & Technical Breakdown – Full narrative of the 6 fatal radiation overdose accidents across clinics in the US and Canada, computer-controlled medical linear accelerator mechanics, removal of backup mechanical relays, PDP-11 assembly code race conditions, “Malfunction 54” screen alerts, and comprehension check questions.

Page 2: Day in the Life Scenario Challenge – Roleplay assignment where students step into the shoes of a Hospital Medical Physicist at Tyler, Texas in March 1986, analyzing operator fast-keying logs, turntable positioning timing windows, uncalibrated dose spikes, and device shutdown protocols.

Page 3: Hands-On Unplugged Simulation & Applied Math – Step-by-step math calculations comparing high-current raw electron beam power versus low-current X-ray target beam power, radiation dose multiplication factors in Rads, and 1-byte integer counter overflow timing windows with 0-255 rollover.

Page 4: Engineering Ethics & Workplace Dilemma – Critical thinking exercise exploring software code reuse versus medical device safety testing, analyzing AECL’s initial denial of software bugs, blaming human operators for “Malfunction 54” errors, re-using Therac-6 assembly code without verification, and FDA recall authority reform.

Page 5: Redesign Brief & Innovation Lab – Creative blueprinting assignment where students design “Therac-25 Medical Linac V-2,” incorporating independent hardware-limit interlocks, redundant optical turntable position switches, secondary watchdog microcontroller circuits, and fail-safe UI keypress delay buffers.

Page 6: Teacher Answer Key & Scoring Rubric – Complete answer key for all analytical questions and math calculations, along with a 10-point grading rubric for evaluating student blueprints on Page 5.

Teacher Benefits:

100% Print-Friendly Format: Clean text layout with zero dark background boxes or awkward formatting for easy editing and printing.

Multi-Day Classroom Value: Designed to cover 3 to 5 full class periods. Perfect for Computer Science, Physical Science, Biomedical Engineering, Health Science, CTE electives, or emergency sub plans.

High-Interest Real-World Content: Combines radiation dosage math, assembly code logic simulation, hospital diagnostic roleplay, software safety ethics, and medical device redesign!

Get this resource as part of a bundle and save up to 20%

A bundle is a package of resources grouped together to teach a particular topic, or a series of lessons, in one place.

Bundle

20 STEM Engineering Disasters Bundle

Transform your classroom with a 120-page bundle covering 20 famous engineering disasters, applied math, telemetry diagnostics, ethics, and redesigns. Full Details: Bring real-world problem-solving, failure analysis, and ethics into your classroom with this comprehensive 20-Unit Engineering Disasters Mega-Bundle! From structural bridge collapses and space shuttle catastrophes to chemical plant meltdowns and fatal software glitches, this 120-plus page collection challenges middle and high school students to analyze real telemetry, perform applied physics and math calculations, navigate high-stakes ethical dilemmas, and redesign safer engineering systems. What’s Included in this 120+ Page Mega-Bundle? Each of the 20 units follows a consistent, student-friendly 6-page printable framework designed for 3 to 5 full class periods of engagement: Page 1: Historical Case Study & Technical Breakdown – Detailed narrative, physical/mechanical principles, key vocabulary, and quick-check comprehension questions. Page 2: Day in the Life Scenario Challenge – Immersive roleplay placing students in control rooms or inspection teams analyzing real-time diagnostic logs and emergency protocols. Page 3: Hands-On Applied Math & Telemetry Simulation – Step-by-step calculations covering structural load limits, thermodynamic heat generation, chemical decay half-lives, binary overflow, and probability margins. Page 4: Engineering Ethics & Workplace Dilemma – Thought-provoking analyses on corporate cost-cutting, whistleblower protection, schedule pressure versus safety, and regulatory reform. Page 5: Redesign Brief & Innovation Lab – Creative blueprinting assignment where students design safer "V-2" systems, write "If/Then" automated computer control logic, and outline structural schematics. Page 6: Teacher Answer Key & Scoring Rubric – Complete answer key for all questions and math problems, plus a standardized 10-point grading rubric for evaluating student redesigns. The 4 Complete Blocks (20 Units Total): Block 1: Civil & Structural Disasters Unit 1: Hyatt Regency Walkway Collapse (1981) — Load paths, dynamic force transfer, and beam physics. Unit 2: Sampoong Department Store Collapse (1995) — Punching shear failure, slab overloading, and structural integrity. Unit 3: San Francisco–Oakland Bay Bridge Failure (1989) — Seismic resonance, expansion joints, and earthquake engineering. Unit 4: St. Francis Dam Failure (1928) — Geotechnical uplift pressure, paleolandslides, and hydraulic engineering. Unit 5: Tacoma Narrows Bridge Collapse (1940) — Aeroelastic fluttering, torsional resonance, and wind dynamics. Block 2: Aerospace & Transportation Catastrophes Unit 6: Apollo 13 Oxygen Tank Explosion (1970) — Thermodynamic pressure, wire insulation degradation, and space survival. Unit 7: Space Shuttle Challenger Disaster (1986) — O-ring glass transition temperature, solid rocket booster blow-by, and flight ethics. Unit 8: Space Shuttle Columbia Re-Entry Breakup (2003) — Reinforced Carbon-Carbon (RCC) strike impact, plasma thermodynamics, and re-entry physics. Unit 9: Sinking of the RMS Titanic (1912) — Brittle steel fracture, watertight bulkhead spillover, and buoyancy physics. Unit 10: The Hindenburg Airship Fire (1937) — Hydrogen gas flammability, static discharge ignition, and airship aerodynamics. Block 3: Industrial & Environmental Disasters Unit 11: The Chernobyl Nuclear Meltdown (1986) — RBMK positive void coefficient reactivity, graphite-tip control rods, and nuclear decay math. Unit 12: The Bhopal Gas Tragedy (1984) — Exothermic runaway reaction kinetics, toxic gas dispersion plume math, and chemical safety. Unit 13: The Deepwater Horizon Oil Spill (2010) — Subsea hydrostatic mud pressure balance, cement bond failure, and BOP shear rams. Unit 14: The Fukushima Daiichi Nuclear Disaster (2011) — Tsunami hydrodynamics, station blackout (SBO), and decay heat thermodynamics. Unit 15: The Texas City Fertilizer Explosion (1947) — Ammonium nitrate decomposition kinetics, confinement pressure, and shockwave physics. Block 4: Computing, Robotics & Modern Failures Unit 16: Therac-25 Radiation Overdose Crises (1985–1987) — Software race conditions, removal of hardware interlocks, and integer overflows. Unit 17: Ariane 5 Flight 501 Rocket Explosion (1996) — 64-bit to 16-bit signed integer overflow, data bus corruption, and legacy code reuse. Unit 18: Mars Climate Orbiter Crash (1999) — Imperial versus Metric unit conversion errors (lbfs vs Ns) and trajectory mechanics. Unit 19: Knight Capital Trading System Crash (2012) — Algorithmic execution loops, dead-code reactivation, and software deployment errors. Unit 20: Boeing 737 MAX MCAS Accidents (2018–2019) — Single Angle of Attack (AoA) sensor dependency, pitch-up aerodynamics, and MCAS software logic. Teacher Benefits: 100% Print-Friendly Format: Clean text layout with zero dark background boxes or awkward formatting for easy editing in Word, Google Docs, or Canva. Cross-Disciplinary Value: Bridges Physics, Chemistry, Physical Science, Computer Science, Environmental Science, Mathematics, and World/US History. Flexible Implementation: Perfect for full STEM units, weekly Case Study Fridays, sub plans, gifted enrichment, CTE courses, or engineering electives.

$60.65

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