Heat kills through the cardiovascular system, the kidneys, the brain. The physician completing a death certificate records what stopped: cardiac arrest, organ failure. One study found 56.8% of medical trainees made exactly this substitution, listing the mechanism rather than the trigger.
Then the OSHA 300 log. Employers fill it out. Employers also run incentive programs rewarding stretches without recordable incidents, programs OSHA itself found suppress reporting. Temporary and undocumented workers frequently never appear on the log at all.
By the time the data reaches the Bureau of Labor Statistics, it shows 33 heat deaths per year. OSHA's own estimate is 559. Every form in the chain is functioning. Each one strips the heat away.