Tunnel Ventilation — Requirement & Field Verification

Field Verification — Return Air
0m/s3.00
5120
0+000m1+000
0+000m1+000
Actual airflow
Airflow adequacy
Shortfall / surplus
Required velocity
Velocity adequacy
Distance to face
Last measurement
TARP: AMBER
Use section-average return-air velocity from a proper traverse
Historical Trend — Airflow Adequacy %

Readings stored in this browser · Required airflow from current calculator inputs · Qactual = Vreturn × Afree

0persons300
0total BHP2,500
25120
Governing requirement: METHANE RISK  →  7,200 m³/min
Q₁ Manpower + Diesel: 1412 m³/min Q₂ Dust / Fumes: 1080 m³/min Q₃ Methane Risk: 7200 m³/min

Interactive comparison of minimum airflow criteria · Tunnel area 25–120 m² · Airflow in m³/min

IS 4756:1978, Cl. 7.4.1 (Reaffirmed 2022) — Fresh air per person & diesel airflow  |  BS 6164:2019 — Return-air velocity for dust/fumes & methane risk  |  DGMS recommendations — Required ventilation air supply in gassy tunnels