Activity 001: Safety Systems Inspection and Emergency Response Drill¶

Activity ID: U3M4-ACT-001 Duration: 35 minutes Objective: Students will inspect all safety systems on the laser cutter, verify their function, and practice the fire emergency response protocol. Group Size: 2-3 students per station Materials Cost: ~$0 (no consumables)

Overview¶

Students perform a comprehensive safety inspection of the laser cutter, testing each interlock and safety system. They then practice the fire emergency response protocol using a simulated scenario. This activity ensures every student can respond correctly to the most likely laser lab emergency before they operate the machine independently.

Materials & Equipment Needed¶

CO2 laser cutter (powered on for interlock testing, no cutting)
Safety inspection checklist (printed, one per group)
Spray bottle of water (for response drill — NOT for actual fire)
CO2 fire extinguisher (identified, NOT discharged — location verification only)
Timer/stopwatch
Simulated emergency scenario cards (laminated)

Instructions & Procedure¶

Phase 1: Safety Systems Inspection (15 min) 1. With the laser cutter POWERED ON but not running a job, test each safety system:

Lid Interlock Test: 2. Close the lid. Attempt to fire the laser (jog pulse or test fire at minimum power on an empty bed) 3. Verify the laser fires with the lid closed: [ ] YES [ ] NO 4. Open the lid. Attempt the same test fire 5. Verify the laser does NOT fire with the lid open: [ ] YES [ ] NO 6. If the laser fires with the lid open: STOP — report immediately, machine must not be used

Emergency Stop Test: 7. Close the lid. Press the EMERGENCY STOP button 8. Verify all motion and laser power stops immediately: [ ] YES 9. Verify the control panel shows an emergency stop state: [ ] YES 10. Reset the emergency stop (twist to release) 11. Verify the machine requires re-homing or re-initialization after E-stop reset: [ ] YES

Exhaust System Verification: 12. Turn on the exhaust system 13. Hold a tissue near the intake inside the cutting chamber — it should flutter strongly 14. Rate the airflow: Strong [ ] Moderate [ ] Weak [ ] None [ ] 15. Listen for unusual sounds (grinding, rattling, reduced motor speed) 16. If using filtered recirculation: check filter status indicators

Water Cooling Verification: 17. Turn on the water chiller 18. Verify temperature display reads 18-22°C: [ ] YES 19. Verify water flow indicator shows circulation: [ ] YES 20. If equipped with a flow interlock: verify the laser will not fire without water flow

Air Assist Verification: 21. Turn on the air assist compressor 22. Hold your hand beneath the laser head nozzle — feel for air flow: [ ] YES 23. Listen for the compressor cycling normally

Phase 2: Fire Safety Equipment Inspection (5 min) 24. Locate the spray bottle of water — verify it is: full [ ], within arm's reach of the machine [ ] 25. Locate the fire extinguisher — verify: correct type (CO2 or dry chemical) [ ], gauge in green zone [ ], accessible [ ], inspection tag current [ ] 26. Locate the nearest exit 27. Measure the distance from the laser cutter to: E-stop [ ], spray bottle [ ], fire extinguisher [ ], exit [ ] 28. All distances should be reachable within 2 seconds — verify with stopwatch

Phase 3: Emergency Response Drill (15 min) 29. Each group performs a tabletop walk-through of three fire scenarios:

Scenario 1: Brief Flame-up - "You see a 2-second flare at the cutting point during a plywood cut" - Correct response: Continue monitoring — brief flares are normal during wood cutting - Group discusses and confirms

Scenario 2: Sustained Flame - "A flame at the cutting point has been burning for 5 seconds and growing" - Each student physically walks through the response (no actual fire): a. Walk to E-stop and press it (time: should be <2 seconds) b. Open the lid c. Pick up the spray bottle and simulate spraying the fire area d. Report: "Fire extinguished" or "escalating — need extinguisher" - Time each student — all should complete steps a-c in under 10 seconds

Scenario 3: Spreading Fire - "The spray bottle has not stopped the fire — it is spreading across the material" - Group walks through: a. Call for help ("Fire in the laser lab!") b. Locate the fire extinguisher c. Describe (do NOT discharge) the PASS technique: Pull pin, Aim at base, Squeeze handle, Sweep d. If fire is not controlled in 10 seconds: evacuate, close the door, call 911

Instructor observes and evaluates each group's drill performance
Debrief: What felt natural? What required thought? What would be hardest in a real emergency?

Discussion Points¶

How quickly could you reach the E-stop from your typical monitoring position?
Why do we test the lid interlock at the START of every session, not just once?
In Scenario 2, why do we press E-stop BEFORE opening the lid?
What is the most important fire prevention measure? (Answer: NEVER leave the laser unattended)

Expected Outcomes¶

All safety systems should pass inspection (if any fail, the machine is taken out of service)
Students should reach the E-stop in under 2 seconds from their monitoring position
Students should complete the fire response sequence (E-stop → lid → spray) in under 10 seconds
Students should correctly describe the PASS extinguisher technique

Assessment Rubric¶

Criterion	Excellent (5)	Proficient (3)	Needs Improvement (1)
Inspection Thoroughness	All safety systems tested and documented with results	Most systems tested, minor documentation gaps	Systems missed or not properly tested
Response Speed	E-stop reached in <2 sec, full response in <10 sec	E-stop in <3 sec, response in <15 sec	E-stop >3 sec or hesitation in response
Protocol Knowledge	Correct response for all three scenarios without prompting	Correct for 2 of 3 scenarios	Incorrect response for multiple scenarios
PASS Technique	Correctly described all four steps in order	3 of 4 steps correct	Unable to describe PASS technique

Safety Considerations¶

This activity involves testing safety systems — follow all standard safety procedures
Do NOT discharge the fire extinguisher during the drill — verbal description of PASS technique only
During interlock testing, no material should be on the bed (prevents accidental cutting)
During E-stop drill, be aware of your surroundings — do not trip or collide while moving quickly
The spray bottle drill uses WATER only — no chemicals

Last Updated: 2026-03-19