Suction in pascals
Suction is a pressure difference, measured in pascals (Pa) or inches of water. It tells you how hard the machine pulls against a sealed opening.
Read the spec sheet
A vacuum cleaner specification table is a list of numbers, each carrying its own unit. Learn what every row means and how to place two models side by side without being misled by a single headline figure.
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Scroll the strip sideways — 6 cards.
Suction is a pressure difference, measured in pascals (Pa) or inches of water. It tells you how hard the machine pulls against a sealed opening.
Airflow is cubic feet per minute (CFM or ft3/min): how much air the machine moves. It is not the same figure as suction.
Air speed is measured in metres per second or miles per hour. It describes how fast air enters the inlet, not how much moves.
Airwatts measure the input power converted into airflow at the end of the cleaning hose. They are the output figure to look for.
Input power is measured in watts. From 2017 no model above 900 watts is permitted in the EU, after models above 1600 watts were banned.
Upright, canister, drum, wet/dry, pneumatic and backpack models each suit a different setting. Configuration belongs in every comparison.
Two independent inventions in 1901 and two successive EU input power thresholds.
| Specification | Unit | Figure from the reference facts |
|---|---|---|
| Suction | pascals (Pa) or inches of water | measured in Pa or in of water |
| Airflow | cubic feet per minute (CFM or ft3/min) | measured in CFM |
| Air speed | metres per second or miles per hour | measured in m/s or mph |
| Output power | airwatts (AW) | input power converted at the hose end |
| Input power | watts | EU limit 900 W from 2017 |
| Earlier input limit | watts | models above 1600 W banned |
| Weight | kilograms or pounds | listed on the sheet |
| Noise | decibels (dB) | listed on the sheet |
Every row on the sheet is a number plus a unit, and the unit tells you what is being measured.
Suction, also called vacuum or water lift, is a pressure difference. It is measured in pascals (Pa) or in inches of water. A higher figure means the machine can pull harder against a sealed opening, which matters when you clean carpet pile or lift debris out of a crevice.
Airflow is a volume: cubic feet per minute, written CFM or ft3/min. Air speed is a velocity, measured in metres per second or miles per hour. These two figures describe how much air moves and how fast, not how hard it pulls.
Airwatts (AW) combine the two. They measure the amount of input power converted into airflow at the end of the cleaning hose, so they tell you how much of the electricity you paid for actually reaches the floor head.
Watts describe what goes in; airwatts describe what comes out at the hose.
Two machines can both draw the same input power and still deliver different airflow, because motor design, ducting and nozzle geometry decide how much of that power becomes useful suction. The EU rules cap input power, not output, so a compliant 900 W machine is not automatically weaker than an older 1600 W one.
When a specification sheet lists only watts, you cannot tell how much of that electricity reaches the cleaning head. Look for the airwatt figure; if it is absent, ask for suction in pascals and airflow in CFM, because those two together describe performance at the nozzle.
Noise and weight sit outside the power figures entirely. A loud machine and a heavy machine cost you in a different currency, so they belong in the comparison even though they have nothing to do with suction.
Every figure on this site comes from the published specification facts for this subject: the 1901 inventions, the EU watt thresholds, the listed units and the configuration types. Nothing else was added, and no model, price or brand appears.
Reference facts
The reference facts cover the invention dates, the EU watt limits, the measurement units and the configuration list.