Description
Sum durations and choose max as the largest level among positive-duration records.
Decibels encode a logarithmic level relative to a reference. Combining periods requires duration-weighted linear energy before converting back to decibels; an arithmetic mean of decibel values generally answers a different question.
Sum durations and choose max as the largest level among positive-duration records.
When to use this tool
Use Environmental Noise Log Energy One Period when combining compatible sound-level periods into one energy-equivalent level.
How to use the tool and how it works
- Enter levelsDb, durations. Keep parallel arrays aligned. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read equivalentDb, totalDuration. Use the output convention below.
Require equally long nonempty levelsDb and durations arrays, with nonnegative durations and at least one positive duration. Sum durations and choose max as the largest level among positive-duration records. Compute energy = sum[(duration/totalDuration)*10^((level-max)/10)], skipping zero-duration records, and equivalentDb = max+10*log10(energy).1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| levelsDb | Compatible sound levels in decibels with matching reference and weighting. | Required. Array of finite number; maximum items 256. |
| durations | Position-aligned nonnegative durations in one common time unit. | Required. Array of finite number; maximum items 256. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| equivalentDb | Energy-equivalent duration-weighted level in decibels. | Required. Finite number. |
| totalDuration | Total Duration | Required. Finite number. |
{
"input": {
"levelsDb": [
60,
70
],
"durations": [
1,
1
]
},
"output": {
"equivalentDb": 67.40362689494243,
"totalDuration": 2
}
}Limitations and assumptions
- Levels must use the same acoustic reference and frequency/time-weighting convention, and durations one time unit. This energy average differs from an arithmetic decibel mean; it adds no day/evening penalty or hearing-risk criterion. Max-shifting improves numerical stability but does not eliminate all underflow.
- 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
Apply a validated acoustic measurement and assessment method when frequency weighting, impulsive noise, exposure standards or time-of-day penalties matter.
References
Similar or alternative tools
- Noise Window Weight Coverage Token
Sum duration*weight across all windows into weightedTotal and only observed windows into weightedCovered.
- Environmental Health Survey Household Base Tool
One explicit household/person denominator correction, not a survey estimator.