| Fluid ounces per minute (fl oz/min) | Milliliters per second (mL/s) |
|---|---|
| 1 Fluid ounce per minute | 0.473551041667 mL/s |
| 2 Fluid ounces per minute | 0.947102083333 mL/s |
| 3 Fluid ounces per minute | 1.420653125 mL/s |
| 4 Fluid ounces per minute | 1.89420416667 mL/s |
| 5 Fluid ounces per minute | 2.36775520833 mL/s |
| 10 Fluid ounces per minute | 4.73551041667 mL/s |
| 20 Fluid ounces per minute | 9.47102083333 mL/s |
| 25 Fluid ounces per minute | 11.8387760417 mL/s |
| 50 Fluid ounces per minute | 23.6775520833 mL/s |
| 100 Fluid ounces per minute | 47.3551041667 mL/s |
| Reference | Fluid ounces per minute (fl oz/min) | Milliliters per second (mL/s) |
|---|---|---|
| A domestic shower | 316.756 fl oz/min | 150 mL/s |
| A kitchen tap | 351.951 fl oz/min | 166.667 mL/s |
| A garden hose | 527.926 fl oz/min | 250 mL/s |
| The Amazon river | 4.41346 × 1011 fl oz/min | 2.09 × 1011 mL/s |
The fluid ounce per minute is a unit of volumetric flow rate equal to one imperial fluid ounce passing a point every minute. Its symbol is fl oz/min. At 28.413 millilitres to the ounce, a minute at this rate delivers a small glass, which places the unit among the deliberate, controlled flows of food, drink and light industry.
Beverage dispensing is its steadiest employer. A post-mix drinks tower is set so that each nozzle delivers a fixed number of fluid ounces per minute, and the ratio of syrup to carbonated water — commonly one to five — is maintained by matching the two rates. A coffee machine's brew rate, a beer line's pour rate and a juice dispenser's throughput are all quoted this way.
Small dosing and metering pumps in food processing carry the same units. Flavourings, colourings, brines and preservatives are injected into a product stream at so many fluid ounces per minute, and the ratio to the main flow is what determines the finished recipe. A pump that drifts by five per cent changes the taste of every package made that shift.
Cleaning and chemical injection follow the same pattern. A dairy or brewery cleaning system meters detergent and sanitiser into circulating water at a rate in fluid ounces per minute, chosen so that the concentration in the loop matches what the supplier specifies for the temperature and contact time being used.
Laboratory and pilot-plant work in Britain and the Commonwealth still meets the unit in older equipment and older standard methods. Rotameters graduated in fluid ounces per minute remain in service, and a technician reading one must remember whether the scale is imperial or American, since the two ounces differ by four per cent.
For orientation, 60 fluid ounces per minute is one fluid ounce per second, 35 fluid ounces per minute is about a litre per minute, and 160 fluid ounces make an imperial gallon. So a dispenser running at 32 fluid ounces per minute fills a gallon in five minutes exactly.
One fluid ounce per minute equals about 28.41 millilitres per minute, about 0.02841 litres per minute, or about 0.01667 fluid ounces per second.
The millilitre per second is a unit of volumetric flow rate equal to one millilitre of fluid passing a point every second. Its symbol is mL/s. Since a millilitre is a cubic centimetre, the unit is identical to the cubic centimetre per second, and the two names are used interchangeably depending on whether the fluid is thought of as a liquid or as a volume of space.
Volumetric flow rate is a volume divided by a time, so it has the dimensions of length cubed per second. That makes it convertible to any other flow unit by a single multiplication, and it also means that a flow rate multiplied by a duration gives the total volume delivered — the arithmetic that underlies every dosing calculation and every water bill.
A millilitre per second is a small but visible flow. A tap dripping steadily produces perhaps a tenth of this; a thin stream from a partly opened tap is a few millilitres per second; a garden hose at full flow is several hundred. In household terms it is the rate at which a teaspoon fills in about five seconds.
The unit belongs to the laboratory and to small machinery. Peristaltic pumps, dosing systems, fuel injectors and analytical instruments all work in this range, and their specifications are written in millilitres per second when the process is fast and in millilitres per minute when it is slow. Where a pump must deliver a precise quantity, the rate and the running time together define the dose.
Human physiology gives useful comparisons. Resting cardiac output is about eighty millilitres per second, urine production averages under a fiftieth of that, and saliva production is around a hundredth. The flow through a single capillary is far smaller still and is measured in cubic millimetres per hour.
Converting to the SI base unit requires care with the powers of ten. One millilitre per second is a millionth of a cubic metre per second, because a millilitre is a millionth of a cubic metre. That factor of a million between the practical unit and the base unit is why flow rates are almost never quoted in cubic metres per second outside hydrology and heavy engineering.
One millilitre per second equals 0.001 litres per second, 60 millilitres per minute, or about 0.0000353 cubic feet per second.