HVAC & Airflow

Tunnel/Mine Ventilation Calculator

Fan airflow for tunnel or mine ventilation by workers and diesel equipment.

Enter your values

Enter the workers underground you are working with.

Enter the total diesel equipment horsepower in hp.

Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.

Results
Required ventilation airflow
44,000 CFM
Worker-based portion
4,000 CFM
Diesel-based portion
40,000 CFM
Fans at 50,000 CFM each
1

Quick answer

Underground ventilation combines a per-worker fresh air allowance with a per-horsepower allowance for diesel equipment exhaust dilution.

CFM = workers x 200 + diesel hp x 100

At a glance

What it doesFan airflow for tunnel or mine ventilation by workers and diesel equipment.
CategoryHVAC & Airflow
Inputs neededWorkers underground, Total diesel equipment horsepower
Main outputRequired ventilation airflow
FormulaCFM = workers x 200 + diesel hp x 100
CostFree — no sign-up, no download

How to use the Tunnel/Mine Ventilation Calculator

  1. 1Count the peak number of workers underground at once.
  2. 2Total the horsepower of diesel equipment operating simultaneously.
  3. 3Apply per-worker and per-horsepower allowances and take the sum, per common mine ventilation guides.

Inputs explained

Workers underground
Enter the workers underground you are working with.
Total diesel equipment horsepower(hp)
Enter the total diesel equipment horsepower in hp.

Worked example

Using the values the calculator loads with:

Inputs

  • Workers underground20
  • Total diesel equipment horsepower400 hp

Results

  • Required ventilation airflow44,000 CFM
  • Worker-based portion4,000 CFM
  • Diesel-based portion40,000 CFM
  • Fans at 50,000 CFM each1

Frequently asked questions

Why per-horsepower for diesel?

Diesel exhaust dilution is regulated separately from human fresh air needs because of DPM (diesel particulate matter) limits.

Does this replace a full ventilation survey?

No — this is a planning estimate; real mine ventilation design also models friction losses and natural ventilation pressure.

What do I need to enter into the Tunnel/Mine Ventilation Calculator?

Just 2 values: workers underground, total diesel equipment horsepower. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.

How does the Tunnel/Mine Ventilation Calculator work out the answer?

Underground ventilation combines a per-worker fresh air allowance with a per-horsepower allowance for diesel equipment exhaust dilution. It applies the formula CFM = workers x 200 + diesel hp x 100 and shows the working so you can check each step by hand.

Is the Tunnel/Mine Ventilation Calculator free, and do I need an account?

It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.

Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.