Understanding Imperial Gallons per Hour to Imperial Gallons per Second Conversion
An Imperial gallon per hour (imp-gal/h) is a UK/imperial volume-flow-rate unit: one Imperial gallon, equal to 4.54609 litres, passing a point each hour. An Imperial gallon per second is a much faster flow, one full Imperial gallon every second; an hour contains 3600 seconds, so the per-second rate is one 3600th of the hourly rate. This conversion is commonly used for high-flow engineering, fire-suppression lines, and instantaneous flow readouts where seconds are the natural time base. The factor is exactly 1/3600, giving 1 imp-gal/h = 0.000277778 imp-gal/s.
Conversion Formula
To convert Imperial Gallons per Hour to Imperial Gallons per Second, multiply the number of Imperial Gallons per Hour by this factor:
Step-by-Step Example
Convert 25 Imperial Gallons per Hour to Imperial Gallons per Second.
Write the formula:
Substitute the value:
Calculate the result:
How to Convert Imperial Gallons per Hour to Imperial Gallons per Second
Follow these steps to turn a flow in Imperial Gallons per Hour into Imperial Gallons per Second.
- Note the flow rate: Start with your value in Imperial Gallons per Hour (imp-gal/h).
- Apply the factor: Multiply that value by 0.000277778, since 1 imp-gal/h = 0.000277778 imp-gal/s.
- Read the result: The product is the equivalent flow in Imperial Gallons per Second (imp-gal/s).
For example, 25 imp-gal/h × 0.000277778 ≈ 0.00694444 imp-gal/s.
Imperial Gallons per Hour to Imperial Gallons per Second conversion table
| Imperial Gallons per Hour (imp-gal/h) | Imperial Gallons per Second (imp-gal/s) |
|---|---|
| 0 | 0 |
| 1 | 0.0002777778 |
| 2 | 0.0005555556 |
| 3 | 0.0008333333 |
| 4 | 0.001111111 |
| 5 | 0.001388889 |
| 6 | 0.001666667 |
| 7 | 0.001944444 |
| 8 | 0.002222222 |
| 9 | 0.0025 |
| 10 | 0.002777778 |
| 15 | 0.004166667 |
| 20 | 0.005555556 |
| 25 | 0.006944444 |
| 30 | 0.008333333 |
| 40 | 0.01111111 |
| 50 | 0.01388889 |
| 60 | 0.01666667 |
| 70 | 0.01944444 |
| 80 | 0.02222222 |
| 90 | 0.025 |
| 100 | 0.02777778 |
| 150 | 0.04166667 |
| 200 | 0.05555556 |
| 250 | 0.06944444 |
| 300 | 0.08333333 |
| 400 | 0.1111111 |
| 500 | 0.1388889 |
| 600 | 0.1666667 |
| 700 | 0.1944444 |
| 800 | 0.2222222 |
| 900 | 0.25 |
| 1000 | 0.2777778 |
| 2000 | 0.5555556 |
| 3000 | 0.8333333 |
| 4000 | 1.111111 |
| 5000 | 1.388889 |
| 10000 | 2.777778 |
| 25000 | 6.944444 |
| 50000 | 13.88889 |
| 100000 | 27.77778 |
| 250000 | 69.44444 |
| 500000 | 138.8889 |
| 1000000 | 277.7778 |
What is the Imperial Gallon per Hour?
The imperial gallon per hour (imp-gal/h) is a unit of volumetric flow rate expressing how many imperial gallons of fluid pass a point in one hour. It is used in the UK and other Commonwealth countries for pumps, fuel consumption, and plumbing flow ratings.
Definition
One imperial gallon per hour equals one imperial gallon of volume divided by one hour (3,600 seconds):
The imperial gallon is defined as exactly 4.54609 litres, so dividing by 3,600 seconds gives 4.54609 / 3600 = 0.00126280 L/s (equivalently 4.54609 L/h).
Origin and History
The imperial gallon was established by the British Weights and Measures Act of 1824, originally defined as the volume of 10 pounds of water at a specified temperature. It was later fixed by reference to the litre. The "per hour" rate arose naturally in the 19th and 20th centuries as a practical measure for pump throughput and fuel usage, hours being a convenient interval for slow, steady flows.
Law and Notable Facts
The imperial gallon (4.54609 L exactly) is legally distinct from and about 20% larger than the US liquid gallon of 3.785411784 L. As a result an imperial gallon per hour is likewise about 20% greater than a US gallon per hour. Since UK metrication, the imperial gallon is no longer a primary trade unit but persists in fuel-economy figures (miles per gallon) and equipment specifications.
Real-World Examples and Conversions
- A small garden or aquarium pump rated at 100 imp-gal/h moves about 454.6 litres of water every hour, roughly 0.126 L/s.
- A domestic tap running at 1 imperial gallon per hour is a bare trickle of about 4.55 L each hour.
- 1 imp-gal/h ≈ 0.833 US gal/h, reflecting the larger imperial gallon.
- A pump moving 220 imp-gal/h delivers about 1,000 L/h, or roughly 0.278 L/s.
What is the Imperial Gallon per Second?
The Imperial gallon per second (imp-gal/s) is a unit of volumetric flow rate, expressing the volume of liquid passing a point each second measured in Imperial (UK) gallons. It appears in British and Commonwealth engineering contexts such as pump ratings, water supply, and fuel handling.
Definition
One Imperial gallon per second equals one Imperial gallon of volume flowing every second. Since the Imperial gallon is defined as exactly 4.54609 litres, the flow rate converts directly to litres per second:
The Imperial gallon is fixed by definition as 4.54609 L exactly (originally the volume of 10 pounds of water). This makes it noticeably larger than the US liquid gallon of 3.785411784 L, so an Imperial gallon per second delivers about 20% more volume than a US gallon per second.
Origin and History
The Imperial gallon was established by the British Weights and Measures Act of 1824, defined as the volume of ten pounds of distilled water at 62 °F. In 1985 the UK redefined it in metric terms as exactly 4.54609 litres. As a rate unit, gallons per second and the more common gallons per minute grew out of the need to specify pump and pipe throughput during the industrial era.
Law and Notable Facts
The Imperial gallon remains a legally recognised unit in the United Kingdom, though the litre is the primary trading unit under metrication. It is distinct from the US gallon: the Imperial gallon (4.54609 L) is roughly 20% larger than the US liquid gallon (3.785 L), so flow figures quoted in "gallons" must always specify which system. A flow of 1 imp-gal/s corresponds to 60 Imperial gallons per minute or 3,600 per hour.
Real-World Examples and Conversions
- A flow of 1 imp-gal/s equals 4.54609 L/s, or about 272.77 litres per minute.
- A typical domestic garden hose delivers well under 1 imp-gal/s; a rate of 1 imp-gal/s (≈16,366 L/h) is closer to a small industrial or firefighting pump.
- 1 imp-gal/s ≈ 1.20095 US gallons per second, reflecting the larger Imperial gallon.
- 1 imp-gal/s ≈ 0.00454609 cubic metres per second, useful when comparing against SI pump specifications.
Frequently Asked Questions
What is the formula to convert Imperial Gallons per Hour to Imperial Gallons per Second?
Multiply the flow in Imperial Gallons per Hour by 0.000277778. In symbols, imp-gal/s = imp-gal/h × 0.000277778.
How many Imperial Gallons per Second are in 1 Imperial Gallon per Hour?
One Imperial Gallon per Hour equals 0.000277778 Imperial Gallons per Second. Working the other way, one Imperial Gallon per Second equals 3600 Imperial Gallons per Hour.
How do I convert 10 Imperial Gallons per Hour to Imperial Gallons per Second?
Multiply 10 by 0.000277778, which gives 0.00277778 Imperial Gallons per Second.
Is this based on the Imperial or US gallon?
It uses the Imperial (UK) gallon of 4.54609 litres, which is about 20% larger than the US liquid gallon of 3.78541 litres. The factor is exactly 1/3600, giving 1 imp-gal/h = 0.000277778 imp-gal/s.
Where is the Imperial Gallon per Hour to Imperial Gallon per Second conversion useful?
It is handy for high-flow engineering, fire-suppression lines, and instantaneous flow readouts where seconds are the natural time base.