Liters per second to air changes per hour
Type a value in L/s to get it in ACH instantly.
54ACH
That's 2.2× as airy as an operating theatre — nothing on our list beats it. One complete change of air takes about 1.111 minutes.
Convert the other way: ACH to L/s
What it means
How fast is the air changing?
Air changes assume the incoming air mixes completely. In practice some of it short-circuits straight to the extract, so the effective rate is lower.
The math
How to convert L/s to ACH
Air changes are flow divided by room volume: ACH = m³/h ÷ room volume. The figures below use the room selected above.
Example: 150 L/s = 54 ACH.
The table below is for Bathroom (10 m³).
Every unit
Your ventilation in every unit
Tables
L/s to ACH conversion table
| L/s | ACH |
|---|---|
| 0.5 L/s | 0.18 ACH |
| 1 L/s | 0.36 ACH |
| 2 L/s | 0.72 ACH |
| 3 L/s | 1.08 ACH |
| 4 L/s | 1.44 ACH |
| 6 L/s | 2.16 ACH |
| 8 L/s | 2.88 ACH |
| 10 L/s | 3.6 ACH |
| 12 L/s | 4.32 ACH |
| 15 L/s | 5.4 ACH |
| 20 L/s | 7.2 ACH |
ACH to L/s conversion table
| ACH | L/s |
|---|---|
| 0.5 ACH | 1.38889 L/s |
| 1 ACH | 2.77778 L/s |
| 2 ACH | 5.55556 L/s |
| 3 ACH | 8.33333 L/s |
| 4 ACH | 11.1111 L/s |
| 6 ACH | 16.6667 L/s |
| 8 ACH | 22.2222 L/s |
| 10 ACH | 27.7778 L/s |
| 12 ACH | 33.3333 L/s |
| 15 ACH | 41.6667 L/s |
| 20 ACH | 55.5556 L/s |
Quick answers
Quick answers
- How many ACH is 1 L/s?
- 1 L/s is 0.36 ACH.
- How many ACH is 10 L/s?
- 10 L/s is 3.6 ACH.
- How many ACH is 150 L/s?
- 150 L/s is 54 ACH.
The units
About these units
Liters per second (L/s)
The unit UK and Australian building codes use.
Air changes per hour (ACH)
How ventilation standards are written: whole room volumes an hour.
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