A water container, water canister or water can is a medium-sized portable container for transport, storage and use of

water Water (chemical formula ) is an Inorganic compound, inorganic, transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living ...

. Large

plastic bottle A plastic bottle is a bottle constructed from high-density or low density plastic. Plastic bottles are typically used to store liquids such as water, soft drinks, motor oil, cooking oil, medicine, shampoo, milk, and ink. The size ranges from v ...

s are sometimes called "canisters". Water canisters can for example be used for

drinking water Drinking water is water that is used in drink or food preparation; potable water is water that is safe to be used as drinking water. The amount of drinking water required to maintain good health varies, and depends on physical activity level, a ...

wastewater Wastewater is water generated after the use of freshwater, raw water, drinking water or saline water in a variety of deliberate applications or processes. Another definition of wastewater is "Used water from any combination of domestic, industrial ...

or showering. Water canisters are used for

excursion An excursion is a trip by a group of people, usually made for leisure, education, or physical purposes. It is often an adjunct to a longer journey or visit to a place, sometimes for other (typically work-related) purposes. Public transportatio ...

camping Camping is an outdoor activity involving overnight stays away from home, either without shelter or using basic shelter such as a tent, or a recreational vehicle. Typically, participants leave developed areas to spend time outdoors in more na ...

, boat trips, in cabins without

tap water Tap water (also known as faucet water, running water, or municipal water) is water supplied through a tap, a water dispenser valve. In many countries, tap water usually has the quality of drinking water. Tap water is commonly used for drinking, ...

, or as a household drinking water reserve in case of emergency. Water canisters come in many different materials and shapes, but are usually made from rigid

plastic Plastics are a wide range of synthetic or semi-synthetic materials that use polymers as a main ingredient. Their plasticity makes it possible for plastics to be moulded, extruded or pressed into solid objects of various shapes. This adaptab ...

with shape as a square or rectangular cube. Typical capacities lie around 5 to 25 liters for household use. If the water is to be used for drinking, the plastic of both the canister,

screw cap A screw cap or closure is a common type of closure for bottles, jars, and tubes. Usage A screw closure is a mechanical device which is screwed on and off of a "finish" on a container. Either continuous threads or lugs are used. It must be engi ...

and tap (also called water spigot) should be food-safe.

Design

Water canisters are made in many different sizes, with some of the most common volumes for household use being for example 5 L, 10 L, 20 L or 25 L. There are no common standardized shapes or sizes. Some canisters are for example designed to easily and sturdily be stacked on top of each other. Stackable water container typically have thicker walls to handle the added weight of being stacked on top of each other. There are also designs which are collapsible and can be folded when not filled with a liquid. Water canisters often have a carrying handle for easier carry. Some canisters are marked with several lines (for example in liters) to indicate the current amount of liquid, but there are also canisters without any level markings. Water canisters are usually made out of plastic, for instance

polyethylene Polyethylene or polythene (abbreviated PE; IUPAC name polyethene or poly(methylene)) is the most commonly produced plastic. It is a polymer, primarily used for packaging ( plastic bags, plastic films, geomembranes and containers including b ...

high-density polyethylene High-density polyethylene (HDPE) or polyethylene high-density (PEHD) is a thermoplastic polymer produced from the monomer ethylene. It is sometimes called "alkathene" or "polythene" when used for HDPE pipes. With a high strength-to-density ratio, ...

, while caps and taps often are made of

polypropylene Polypropylene (PP), also known as polypropene, is a thermoplastic polymer used in a wide variety of applications. It is produced via chain-growth polymerization from the monomer propylene. Polypropylene belongs to the group of polyolefins a ...

or polyethylene. Some canisters have air vents which can be opened to avoid

sloshing In fluid dynamics, slosh refers to the movement of liquid inside another object (which is, typically, also undergoing motion). Strictly speaking, the liquid must have a free surface to constitute a slosh dynamics problem, where the dynamics of ...

while emptying the container. Large water canisters may require a bung wrench to be opened (similar to

barrels A barrel or cask is a hollow cylindrical container with a bulging center, longer than it is wide. They are traditionally made of wooden staves and bound by wooden or metal hoops. The word vat is often used for large containers for liquids, u ...

). File:Niger, Niamey, Taladje (Rue TJ-6), water point.JPG, Square containers (here around 25 L) can be stacked more efficiently than cylindrical contains for transport. File:Water cans for sale.JPG, Cylindrical water jugs of the type used on

water dispenser A water dispenser, known as water cooler (if used for cooling only), is a machine that dispenses and often also cools or heats up water with a refrigeration unit. It is commonly located near the restroom due to closer access to plumbing. A drain ...

s (typically around 15-30 liters). File:Fetching water at the well.jpg, People in Uganda filling up water canisters (here around 5-20 L). File:2017-07-28 (057) Trailer with water tank in Frankenfels, Austria.jpg,

Intermediate bulk container Intermediate bulk containers (also known as IBC tank, IBC tote, IBC, or pallet tank) are industrial-grade containers engineered for the mass handling, transport, and storage of liquids, semi-solids, pastes, or solids. The two main categories of I ...

s can be used as larger water canisters, typically holding around 1000 liters.

Thread types

Threads for caps and taps are standardized to some degree, with many European designs being based on various DIN standard sizes. Some common thread diameters on European water canisters are 40 mm, 45 mm, 50 mm and 60 mm. A tap can either be an integrated part of the container (for example protected by a ridge) or an accessory. On some designs, the tap is supposed to be replaced with a cap for storage or transport. A table of some common water canister thread types is shown below:Bürkle catalogue 2020 - Thread adapters
/ref> {, class="wikitable sortable" style="text-align: left;" ! Type ! Opening diameter (mm) ! External thread diameter (mm) ! Pitch (mm) , - , 51 mm DIN 51 , 50.5 , 53 , 5 , - , 61 mm DIN 60 , 55.8 , 59-60 , 6 , - , 61 mm DIN 61 , 55.8 , 61 , 6 , - , 71 mm DIN 71 , 66.5 , 71 , 6 , - , 96 mm DIN 96 , ? , ? , ? , - , BSP / R2" steel drum fine thread , 57.5 , 59 , 2.2 , - , 63 mm, 64 mm BSI , 60 , 64.5 , 5 , - , 35 mm , 32.7 , 33.5 , 3 , - , 2″ coarse Mauser L-ring , 65 , 69.5 , 5.5 , - , Tri-Sure, {{cvt, 2, in, mm coarse thread , 52.5 , 56 , 3.5 , - , US drum thread , 57.5 , 63.2 , 4.25 , -

Weight

The weight of just the container itself can for many practical purposes be considered negligible compared to the weight of the liquid it holds. Under this assumption, one can assume that the volume of a canister filled with water measured in liters will correspond to the same mass in kilograms. This will also hold true for other liquids with similar density to water. For example, a full 5 L water canister will thus weight a little over 5 kg, while a full 25 L water canister will weigh a little over 25 kg.

Hygiene

With long-term storage, a

biofilm A biofilm comprises any syntrophic consortium of microorganisms in which cells stick to each other and often also to a surface. These adherent cells become embedded within a slimy extracellular matrix that is composed of extracellular ...

can form on the inside of the canister, especially of the canister is exposed to sunlight. In this case, having a canister with a large diameter opening can make cleaning easier. Many waster canisters are made of UV resistant food-grade plastic to limit UV damage to the container, as well as limit biological growth. Water canisters are often blue as this is effective at blocking UV light. For long term storage, it is recommended to store water containers in a dark room to limit bacterial growth. This is especially important with clear containers, as these let through light. Typical plastics used in food-grade water containers are polyethylene terephthalate (PETE or PET, recycle code 1),

(PVC, recycle code 2) and

low-density polyethylene Low-density polyethylene (LDPE) is a thermoplastic made from the monomer ethylene. It was the first grade of polyethylene, produced in 1933 by Imperial Chemical Industries (ICI) using a high pressure process via free radical polymerization. Its ...

(LDPE, recycle code 4). The type of plastic should be identifiable from recycle codes stamped on the container. Care should be taken to know the history of what has been stored previously on the containers, as well as making sure that containers are cleaned properly before use.

Use for other liquids

Some water canisters and similar canisters can be suitable for storing other liquids, like for example many types of acids, bases, salt solutions and oils. File:5l Diesel Exhaust Fluid canister .jpg, Diesel exhaust fluid packed in two 5L plastic bottles (canisters). File:Bidon de 10 litres d'AdBlue.jpg, Diesel exhaust fluid packed in two 10L plastic bottles (canisters).

References

External links

Container thread sizes – S.C.A.T. Europe (Safety-Center-Analyses-Technology)
Containers