Description
Return ideal case-air excess decay for one interval.
Conservation records distinguish sampled support, retained material, environmental bands and time-dependent model terms. A caller-supplied band or decay constant does not establish an appropriate preservation target. Local bookkeeping and simple exponential response models require separate evidence about the object and its environment.
Return ideal case-air excess decay for one interval.
When to use this tool
Use Display Case Air Exchange One Interval when checking the stated sampling, material balance or environmental-response convention.
How to use the tool and how it works
- Enter airChangesPerHour, hours, initialExcess. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read retainedFraction, finalExcess. Use the output convention below.
Return ideal case-air excess decay for one interval. Require airChangesPerHour/hours >= 0; retainedFraction = exp(-rate*hours), finalExcess = initialExcess*retained.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| airChangesPerHour | Air Changes Per Hour | Required. Finite number; minimum 0. |
| hours | Hours | Required. Finite number; minimum 0. |
| initialExcess | Initial Excess | Required. Finite number. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| retainedFraction | Retained Fraction | Required. Finite number. |
| finalExcess | Final Excess | Required. Finite number. |
{
"input": {
"airChangesPerHour": 0.5,
"hours": 2,
"initialExcess": 100
},
"output": {
"retainedFraction": 0.36787944117144233,
"finalExcess": 36.787944117144235
}
}Limitations and assumptions
- This assumes well-mixed first-order exchange with a fixed background; actual case leakage, pollutant sources and conservation suitability are not inferred.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Review verified records and the object-specific preservation assessment with a qualified conservator for actual sampling, display or treatment decisions.
References
Similar or alternative tools
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