| Cubic meters per minute (m³/min) | Fluid ounces per second (fl oz/s) |
|---|---|
| 1 Cubic meter per minute | 586.584662131 fl oz/s |
| 2 Cubic meters per minute | 1173.16932426 fl oz/s |
| 3 Cubic meters per minute | 1759.75398639 fl oz/s |
| 4 Cubic meters per minute | 2346.33864852 fl oz/s |
| 5 Cubic meters per minute | 2932.92331065 fl oz/s |
| 10 Cubic meters per minute | 5865.84662131 fl oz/s |
| 20 Cubic meters per minute | 11731.6932426 fl oz/s |
| 25 Cubic meters per minute | 14664.6165533 fl oz/s |
| 50 Cubic meters per minute | 29329.2331065 fl oz/s |
| 100 Cubic meters per minute | 58658.4662131 fl oz/s |
| Reference | Cubic meters per minute (m³/min) | Fluid ounces per second (fl oz/s) |
|---|---|---|
| A domestic shower | 0.009 m³/min | 5.27926 fl oz/s |
| A kitchen tap | 0.01 m³/min | 5.86585 fl oz/s |
| A garden hose | 0.015 m³/min | 8.79877 fl oz/s |
| The Amazon river | 12540000 m³/min | 7.35577 × 109 fl oz/s |
The cubic metre per minute is a unit of volumetric flow rate equal to one cubic metre passing a point every minute. Its symbol is m³/min. It occupies the middle ground of industrial air handling: large enough for a factory's compressed-air main, small enough that the number stays in two or three digits.
Compressors are its most familiar users. A workshop screw compressor delivers 1 to 10 cubic metres per minute of free air, a large industrial machine 50 or more, and the rating is always given as free air delivery — the volume measured at atmospheric conditions rather than at the compressed pressure, because that is what the tools downstream actually consume.
Sizing a compressed-air system is an exercise in adding these numbers. Each tool has a consumption figure: an impact wrench 0.6 cubic metres per minute, a spray gun 0.3, a sandblasting nozzle several. Total them, apply a duty factor because they do not all run at once, add a margin for leaks, and the result is the compressor the workshop needs.
Mine and tunnel ventilation is quoted the same way. Regulations set a minimum air quantity per person and per unit of diesel power underground, and a working face may require 20 to 50 cubic metres per minute. The main fan at the surface handles the sum of every face, which is why the unit spans four orders of magnitude within a single industry.
Blowers, dust extraction and pneumatic conveying complete the picture. A woodworking dust extractor is rated at 20 to 60 cubic metres per minute, a bag filter for a cement plant at thousands, and a pneumatic conveyor is designed around the air velocity in the pipe, which the flow and the pipe cross-section together determine.
The conversion to its neighbours is easy in both directions. Sixty cubic metres per minute is one cubic metre per second, and one cubic metre per minute is a thousand litres per minute. That last relation is why the same fan can appear in a European catalogue as 1,200 litres per second and in another as 72 cubic metres per minute.
One cubic metre per minute equals about 0.01667 cubic metres per second, 1,000 litres per minute, or about 35.31 cubic feet per minute.
The fluid ounce per second is a unit of volumetric flow rate equal to one imperial fluid ounce passing a point every second. Its symbol is fl oz/s. The imperial fluid ounce is 28.413 millilitres, defined as one twentieth of an imperial pint, so this unit describes the flow of a steady pour rather than a plumbing system.
Its natural home is the bar and the kitchen. A pint glass filled in twelve seconds is being poured at about 1.7 fluid ounces per second, and a bartender free-pouring spirits counts seconds against a known rate to measure a shot without a jigger. Automatic dispensing guns on a bar are calibrated in exactly these terms so that a portion is repeatable across a busy evening.
Beverage plants use it for filling heads. A bottling line filling half-litre bottles at 200 bottles a minute must deliver about 59 fluid ounces per second in total, divided among however many heads the filler carries. Each head's individual rate determines the fill time, and the fill time determines how fast the carousel can turn.
The unit persists in British and Commonwealth food and drink specifications, where recipes, dispense rates and portion controls have been written in fluid ounces for generations. A soft-drink dispenser is set so that the syrup and the carbonated water arrive in a fixed ratio, and both rates are naturally quoted in fluid ounces per second.
A warning belongs here: the American fluid ounce is 29.574 millilitres, about four per cent larger than the imperial one, and the American pint holds sixteen of them against the imperial twenty. A flow rate quoted in fluid ounces per second therefore differs by four per cent between the two systems, and by twenty per cent when the same number of ounces is called a pint.
For a sense of scale, 35 fluid ounces per second is about a litre per second, and one fluid ounce per second fills a pint in twenty seconds and a gallon in a little under three minutes. It is the rate of a fast tap or a generous jug.
One fluid ounce per second equals about 28.41 millilitres per second, about 0.02841 litres per second, or about 1.734 cubic inches per second.