Enter Air Toxics Data
Use the responsive calculator grid below. Large screens show three columns, smaller screens show two, and mobile shows one.
Example data table
These sample cases show how the calculator can summarize emissions, annual mass, and simple risk screening indicators.
| Pollutant | Inlet Conc. (mg/m3) | Flow (m3/hr) | Control (%) | Annual Emission (kg/yr) | Hazard Quotient | Cancer Risk |
|---|---|---|---|---|---|---|
| Benzene | 35.00 | 18,000 | 92.0 | 302.400 | 0.000397 | 9.282E-8 |
| Formaldehyde | 18.00 | 12,000 | 88.0 | 186.624 | 0.000600 | 7.020E-8 |
| Toluene | 50.00 | 15,000 | 95.0 | 187.500 | 0.000018 | 0.000E+0 |
Formula used
These equations provide a practical engineering screen. Regulatory projects may require site-specific flow verification, pollutant speciation, stack testing, and refined atmospheric dispersion modeling.
How to use this calculator
- Enter the pollutant name for clear reporting and export output.
- Input the uncontrolled stack concentration and actual exhaust flow.
- Provide gas temperature, absolute pressure, and moisture for standard dry correction.
- Enter the control efficiency of the abatement device.
- Add annual operating hours to estimate yearly mass emissions.
- Use molecular weight when you want a ppmv conversion.
- Enter a screening reference concentration for noncancer review.
- Enter a unit risk factor and screening dispersion factor for simple cancer risk estimation.
- Click the calculate button to show results above the form.
- Use the CSV or PDF buttons to export the reported results.
Frequently asked questions
1) What does this air toxics calculator estimate?
It estimates controlled outlet concentration, mass emission rate, standard dry concentration, annual emissions, ambient screening concentration, hazard quotient, and simple cancer risk indicators.
2) Is this suitable for final permit applications?
No. It is a screening and engineering review tool. Final submittals often need test data, approved emission factors, and refined dispersion modeling.
3) Why is moisture entered separately?
Moisture affects dry gas correction. Many regulations compare emissions on a dry basis, so wet exhaust flow should be adjusted before reporting corrected concentration.
4) Why does the chart use a logarithmic scale?
Stack concentrations are often far larger than ambient screening values. A logarithmic scale keeps all three stages visible on one graph.
5) What is the hazard quotient?
It is the estimated ambient screening concentration divided by a reference concentration. Values below one usually indicate lower noncancer screening concern.
6) What does the cancer risk value represent?
It is a simple lifetime risk estimate from multiplying ambient concentration by a unit risk factor. Use it as a screening metric only.
7) Can I use ppmv instead of mg/m3?
The calculator accepts mg/m3 as the main concentration input. It also estimates ppmv from molecular weight so you can compare values across units.
8) What dispersion factor should I enter?
Use a screening factor from your method, policy, or prior modeling basis. Different stack heights and sites can change the appropriate value significantly.