Radium Tritium Lume Transition Lookup
Return an official-source fact about radium and tritium watch-lume materials, the approximate transition, hazards, or dating limitations.
Description
Historical radioluminescent dials used radioactive sources, and later materials changed exposure characteristics.
Historical radioluminescent dials used radioactive sources, and later materials changed exposure characteristics. A transition period cannot date an individual watch by itself.1, 2
Return an official-source fact about radium and tritium watch-lume materials, the approximate transition, hazards, or dating limitations.
When to use Radium Tritium Lume Transition Lookup
Use this tool to return an official-source fact about radium and tritium watch-lume materials, the approximate transition, hazards, or dating limitations.
Choose a supported lookup focus or prepare the measured values, documented evidence and caller-selected limits requested. Use the exact field names and confirm their units or date format.
How to use Radium Tritium Lume Transition Lookup and understand its results
- Choose a supported lookup focus or prepare the measured values, documented evidence and caller-selected limits requested. Use the exact field names and confirm their units or date format.
- Enter transitionFocus using the field table and calculation rules, then run the tool.
- Read keyDate, transitionFocus, verifiedStatement. The explanation below defines the units, signs, ordering and any flags or placeholder values.
- If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.
| Input field | Meaning | Value type; see rules below | Requirement |
|---|---|---|---|
| transitionFocus | Radium-to-tritium lume transition focus | string; one of "materials", "transition", "laterIsotopes", "healthHazard", "datingCaution" | Required |
Select one supported focus from the input table and run the lookup. Match the exact case-sensitive enum value; no trimming, synonyms or free-text search is applied. Return the selected focus and its stored transition/material/hazard statement and historical/context label. keyDate, where present, can be a historical date, period or contextual label rather than a parseable date.
result=stored entry for exact selected focus Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| keyDate | Key date or status | string |
| transitionFocus | Radium-to-tritium lume transition focus | string |
| verifiedStatement | Verified lume statement | string |
{
"input": {
"transitionFocus": "transition"
},
"output": {
"keyDate": "approximately 1968 for radium timepieces",
"transitionFocus": "transition",
"verifiedStatement": "The US NRC report states that radium had not been used in radioluminescent watches since approximately 1968; this is not a universal brand cutoff."
}
}Limitations and assumptions
No isotope, radiation dose, dial originality or exact production cutoff is identified. Do not dismantle suspected radium timepieces; consult qualified handling guidance. This is a fixed local table; it does not fetch sources or update statements at runtime.
Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Extremely large text inputs are rejected. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.
Alternative or Complementary methods
Use Radioluminescent Brightness Half Life Calculator: Apply an explicit radioactive half-life model to caller-supplied initial brightness without comparing different lume chemistries or claiming measured nighttime luminance. For a complementary task, use Refinished Dial Evidence Screen: Organize explicit evidence into replacement, refinished original, supported original, or insufficient-evidence dial classifications without inventing a value penalty.
Further background: Radioactivity in Antiques.
References
-
Radium Tritium Lume Transition Lookup — tool.io
-
Radioactivity in Antiques — US Environmental Protection Agency
Similar or alternative tools
- Radioluminescent Brightness Half Life Calculator
Apply an explicit radioactive half-life model to caller-supplied initial brightness without comparing different lume chemistries or claiming measured nighttime luminance.
- Refinished Dial Evidence Screen
Organize explicit evidence into replacement, refinished original, supported original, or insufficient-evidence dial classifications without inventing a value penalty.