Chlorine vs. Chloramine — What's the Difference?

A chemical element used as a primary disinfectant in water treatment.

A compound of chlorine and ammonia used as a secondary disinfectant in water.

Known for its strong, pungent odor that is often noticeable in swimming pools.

Its use requires careful balance and monitoring to maintain effectiveness without affecting water quality.

Can react with organic compounds in water to form potentially harmful by-products.

Produces fewer disinfection by-products, reducing health risks associated with long-term exposure.

Used not only in water treatment but also in the production of paper products, dyes, and textiles.

Less aggressive and corrosive than chlorine, making it safer for long-term use in infrastructure.

Chlorine is a chemical element with the symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate between them.

Maintains better residual disinfectant qualities in extensive piping systems.

A highly irritating, greenish-yellow halogen element, existing as a diatomic gas, Cl2, and capable of combining with nearly all other elements, produced principally by electrolysis of sodium chloride and used widely to disinfect water, as a bleaching agent, and in the manufacture of many important compounds including chlorates, sodium hypochlorite, and chloroform. Atomic number 17; atomic weight 35.453; freezing point -100.5°C; boiling point -34.04°C; specific gravity 1.56 (-33.6°C); valence 1, 3, 5, 7. See Periodic Table.

An unstable colorless liquid, NH2Cl, used in making hydrazine and as a chlorine source for water treatment.

A toxic, green, gaseous chemical element (symbol Cl) with an atomic number of 17.

Any of several aromatic sulfonamide salts containing chlorine, used medicinally as antiseptics.

(countable) A single atom of this element.

(chemistry) any of a class of unstable compounds of nitrogen and chlorine R₁R₂NCl; also the parent compound NH₂Cl, used to manufacture hydrazine, and as the antiseptic chloramine-T

One of the elementary substances, commonly isolated as a greenish yellow gas, two and one half times as heavy as air, of an intensely disagreeable suffocating odor, and exceedingly poisonous. It is abundant in nature, the most important compound being common salt (Sodium chloride). It is powerful oxidizing, bleaching, and disinfecting agent. Symbol Cl. Atomic weight, 35.4.

Any of several compounds containing chlorine and nitrogen; used as an antiseptic in wounds

A common nonmetallic element belonging to the halogens; best known as a heavy yellow irritating toxic gas; used to purify water and as a bleaching agent and disinfectant; occurs naturally only as a salt (as in sea water)

Requires careful handling due to its highly reactive and corrosive nature.

Chlorine can be added as a gas or in a dissolved form, while chloramine is formed by mixing chlorine with ammonia under controlled conditions.

Both chlorine and chloramine are used to disinfect water, but chlorine is used primarily for rapid disinfection, while chloramine provides longer-lasting water quality control.

Chloramine is preferred in some systems because it provides longer-lasting disinfection with fewer by-products, which reduces health risks.

Yes, chlorine can cause a strong taste and smell, whereas chloramine has a much lesser impact on the sensory qualities of water.

Chlorine can produce harmful by-products like THMs and HAAs, which are associated with cancer risks; chloramine produces fewer of these compounds but can still pose risks if not properly managed.

Chlorine is cheaper and easier to use, but the long-term benefits of chloramine can outweigh its higher initial cost due to reduced by-product management and infrastructure corrosion.

Both chemicals can be toxic to aquatic life; measures must be taken to ensure that water containing these disinfectants does not enter natural water bodies without adequate treatment.

Bottled water is typically treated using processes that do not leave residual disinfectants, such as distillation or reverse osmosis.

Environmental regulations mandate limits on disinfection by-products, influencing how and when each chemical is used in public water systems.

Chlorine is more potent and faster acting than chloramine, but chloramine offers more consistent and long-lasting disinfection.

Both chemicals require careful handling to avoid exposure and inhalation risks; protective gear and proper ventilation are essential.

Alternatives include UV light treatment and ozone treatment, which do not introduce chemicals into the water but may be more expensive and technologically demanding.

Yes, activated carbon filters and reverse osmosis systems are effective at removing both chlorine and chloramine from tap water.

Chlorine can be more corrosive to plumbing and appliances, whereas chloramine is less so but can still cause issues like pitting and degradation over time.

A combination approach can be used, starting with chlorine for immediate disinfection followed by chloramine to maintain longer-lasting water quality throughout the distribution system.