Dosing generally applies to feeding chemicals or medicines in small quantities into a process fluid or to a living being at intervals or to atmosphere at intervals to give sufficient time for the chemical or medicine to react or show the results.
In the case of human beings or animals the word dose is generally used but in the case of inanimate objects the word dosing is used. The term dose titration, referring to stepwise titration of doses until a desired level of effect is reached, is common in medicine.
The word dosing is very commonly used by engineers in thermal power stations, in water treatment, in any industry where steam is being generated, and in building services for heating and cooling water treatment. Dosing procedures are also in vogue in textile and similar industries where chemical treatment is involved.
Commercial swimming pools also require chemical dosing in order to control pH balance, chlorine level, and other such water quality criteria. Modern swimming pool plant will have bulk storage of chemicals held in separate dosing tanks, and will have automated controls and dosing pumps to top up the various chemicals as required to control the water quality.
In a power station treatment chemicals are injected or fed to boiler and also to feed and make up water under pressure, but in small dosages or rate of injection. The feeding at all places is done by means of small capacity dosing pumps specially designed for the duty demanded.
In building services the water quality of various pumped fluid systems, including for heating, cooling, and condensate water, will be regularly checked and topped up with chemicals manually as required to suit the required water quality. Most commonly inhibitors will be added to protect the pipework and components against corrosion, or a biocide will be added to stop the growth of bacteria in lower temperature systems. The required chemicals will be added to the fluid system by use of a dosing pot; a multi-valved chamber in which the chemical can be added, and then introduced to the fluid system in a controlled manner.
The feeding of chemicals in agriculture has also become common due to technology developments. However agricultural dosing is done by means of hand held pressure spray pumps
Sometimes aerial spraying of chemicals by fixed quantities at intervals or dosing is also adopted for agricultural spraying or for atmospheric spraying for eliminating certain types of harmful insects.