Radium dial

Common card · No. 210867

Radium dials are watch, clock and other instrument dials painted with luminous paint containing radium-226 to produce radioluminescence. Radium dials were produced throughout most of the 20th century before being replaced by safer tritium-based luminous material in the 1970s and finally by non-toxic, non-radioactive strontium aluminate–based photoluminescent material from the middle 1990s. The gruesome and often fatal radium jaw injuries suffered by early dial painters in the United States became a cause célèbre for occupational safety and labor law in the opening decades of the 20th century.

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