Conversion from Fluid ounces per second to Liters per second

Information about the Fluid ounce per second (fl oz/s)

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.

Information about the Liter per second (L/s)

The litre per second is a unit of volumetric flow rate equal to one litre passing a point every second. Its symbol is L/s. It is the unit of pumps, drains and ventilation — the scale at which a flow is large enough to be a design problem but small enough to belong to a single building.

A litre per second is a substantial stream. A kitchen tap fully open delivers about a fifth of it, a bath fills at roughly a third, and a fire hose runs at ten to twenty times as much. In visual terms it is a jet about as thick as a thumb moving briskly, and it would fill a domestic bath in about two minutes.

Building services are specified in this unit throughout Europe. Ventilation rates are given as litres per second per person — around eight to ten in an office, more in a room where people cook or exercise — and a designer multiplies that figure by the number of occupants to size the fans and the ductwork. The same unit describes rainwater drainage, where a roof's area and the local rainfall intensity together determine the flow a downpipe must carry.

Pumps are rated the same way. A domestic circulating pump moves a fraction of a litre per second, a borehole pump a few, and a large sewage pump hundreds. Because the power a pump needs is the flow multiplied by the pressure it must overcome, this figure sits at the centre of every pump calculation.

For gases the unit describes compressors and blowers, though there the volume depends on pressure and temperature and so must be stated at defined conditions. A compressor rated at fifty litres per second of free air is measured with the air at atmospheric pressure, and the same machine moving compressed air is shifting a far smaller volume.

A litre per second is a thousandth of a cubic metre per second, which is why hydrologists and building engineers rarely use the same unit even when they are describing the same water. A river carrying a cubic metre per second is carrying a thousand litres per second, and both figures are correct.

One litre per second equals 1,000 millilitres per second, 60 litres per minute, or about 0.0353 cubic feet per second.