Ventilation Air Quantity
Screen fully mixed steady dilution against supplied concentrations; shared contaminant constraints use maximum flow, not a sum, and do not certify mine safety.
Description
Steady well-mixed dilution balances contaminant generation against the permitted concentration increase above intake air.
Steady well-mixed dilution balances contaminant generation against the permitted concentration increase above intake air. Multiple contaminants may impose different flow requirements.
The tool returns contaminantRequiredFlowsM3PerSecond (contaminant required flows m3 per second); governingFreshAirM3PerSecond (governing fresh air m3 per second). Input measurements and model parameters are supplied by the caller; the tool computes the stated summary rather than acquiring those measurements.
When to use Ventilation Air Quantity
Use Ventilation Air Quantity when you already have contaminantGenerationMgPerSecond, intakeConcentrationsMgPerM3, comparisonConcentrationsMgPerM3, minimumFreshAirM3PerSecond and want contaminantRequiredFlowsM3PerSecond, governingFreshAirM3PerSecond. This is useful for checking a supplied calculation, documenting a measurement convention, or comparing observations prepared on the same basis.
How to use Ventilation Air Quantity and understand its results
- Enter contaminantGenerationMgPerSecond, intakeConcentrationsMgPerM3, comparisonConcentrationsMgPerM3, minimumFreshAirM3PerSecond using the field table below. Match the units, ordering and data boundaries described in the calculation.
- Run the tool after checking the stated bounds and matching paired observations or categories. A malformed request gives a tool error rather than a usable measurement.
- Read contaminantRequiredFlowsM3PerSecond, governingFreshAirM3PerSecond. Use the calculation and interpretation below to distinguish amounts, ratios, signs and decision flags where applicable.
- Review the supplied parameters and assumptions before using the result in a report or comparing it with another observation.
| Input field | Meaning | Value type and bounds | Requirement |
|---|---|---|---|
| contaminantGenerationMgPerSecond | Contaminant generation mg per second | list of number | Required |
| intakeConcentrationsMgPerM3 | Intake concentrations mg per m3 | list of number | Required |
| comparisonConcentrationsMgPerM3 | Comparison concentrations mg per m3 | list of number | Required |
| minimumFreshAirM3PerSecond | Minimum fresh air m3 per second | number | Required |
Use aligned nonempty lists, nonnegative generation and intake, and comparisons strictly above each intake concentration.
Q[i] = generationMg/s/(comparisonMg/m³−intakeMg/m³); governing = max(minimumFreshAir,all Q) The symbols refer to the supplied quantities or generated values described above; unit conversions and comparison boundaries follow the stated implementation.
{
"input": {
"contaminantGenerationMgPerSecond": [
100,
60
],
"intakeConcentrationsMgPerM3": [
1,
0
],
"comparisonConcentrationsMgPerM3": [
3,
3
],
"minimumFreshAirM3PerSecond": 10
},
"output": {
"contaminantRequiredFlowsM3PerSecond": [
50,
20
],
"governingFreshAirM3PerSecond": 50
}
}Limitations and assumptions
Comparison concentrations are caller-selected. Incomplete mixing, transient peaks, interacting contaminants and legal compliance are not evaluated.
Numerical inputs must be finite. The tool checks its declared input shape and calculation constraints; those checks do not verify the quality, calibration or representativeness of the supplied observations.
Alternative or Complementary methods
Ventilation Pressure Drop: Sum series Atkinson resistances in Pa/(m³/s)² and compute pressure drop/air power; parallel networks and fans are not solved. Heat Removal Ventilation: Balance sensible heat against air heat capacity and caller permitted rise; latent heat, humidity and worker heat-stress criteria are excluded.
Methodological background: Introduction to Mine Ventilating Principles and Practices.1
References
-
Introduction to Mine Ventilating Principles and Practices — U.S. Bureau of Mines, Bulletin 589
Similar or alternative tools
- Ventilation Pressure Drop
Sum series Atkinson resistances in Pa/(m³/s)² and compute pressure drop/air power; parallel networks and fans are not solved.
- Heat Removal Ventilation
Balance sensible heat against air heat capacity and caller permitted rise; latent heat, humidity and worker heat-stress criteria are excluded.