Testing shows automotive glassbreakers can't break modern automotive glass

Use Cases & Threat Models

• People mention buying glassbreakers for fears like a “crazed Uber driver” or sinking in a lake; others argue most modern cars can’t truly “lock you in” without modifications, except via child safety locks.
• Some note that in water immersions, the main issue is water pressure and damaged doors, not door locks.
• Several comments stress that bystanders, not the trapped driver, are the more realistic users of such tools (e.g., pulling someone from a burning or crashed car).

Tempered vs Laminated Glass & Regulation

• Discussion centers on FMVSS 226 as an ejection-mitigation performance standard, not a laminated-glass mandate: manufacturers can comply via side airbags, laminated glass, or other countermeasures.
• Many cars (especially older and non-premium models) still have tempered side glass; newer or higher trims more often use laminated front side windows.
• Laminated glass resists shattering and ejection, improves noise and UV protection, and reduces glass-spray injuries, but is much harder to breach for escape or rescue.

Safety Tradeoffs

• One side calls “unbreakable” glass morally wrong and emphasizes entrapment/fatality risk.
• Others respond that all safety systems (seatbelts, airbags, lane assist) have nonzero fatality side effects, but are justified by overall risk reduction, especially for rollovers and partial ejections.
• There’s disagreement on how often window escape is realistically needed versus how often ejection prevention saves lives; exact frequencies are noted as unclear.

Effectiveness of Glassbreakers & Alternatives

• Thread agrees most consumer glassbreakers (including “EDC” gadgets) are designed only for tempered glass and largely fail on laminated glass; in tests, many struggled even with tempered.
• Spark plug ceramic, “ninja rocks,” and ceramic punches are said to work well on tempered, but lamination’s plastic interlayer remains the real barrier.
• Suggested alternatives: specialized cutting tools (e.g., Keetch, rescue cutters), axes/tomahawks, or firefighter-style methods—but these are bulkier, slower, and unrealistic for typical drivers.
• Consensus: emergency services can get through laminated glass, but it takes more time, effort, and tools than most people carry.

Practical Advice & Broader Safety

• Check markings on your own windows to know where you have tempered vs laminated glass; patterns vary by model, trim, and front/rear.
• Emphasis from an automotive worker: the best “tool” is crash avoidance—drive sober, manage mood, beware left turns, limit nighttime screen use, and practice using manual door releases on cars with electronic latches.