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Sherwood Valve has become one of the industry’s most famous names, providing valves for a range of medical, industrial, and municipal applications. But it is the Sherwood chlorine gas cylinder valve we’re focusing on today — why is it so important to drinking water treatment in America?

But first, we’re going to take a look at chlorine water disinfection, discovering more about why this has become so important to American society.

What Is Chlorine Water Disinfection?

To say that chlorine water treatment changed everything is…well, yes, it’s a bit of an overstatement, but it changed a lot about American healthcare and society as a whole. Before chlorine treatment became commonplace, the United States was frequently in the grip of waterborne diseases. Until the introduction of chlorine to drinking water supplies, typhoid fever was killing 25 out of every 100,000 Americans — roughly double the numbers killed in automobile accidents in 2021. Legionnaires’ disease and other illnesses were also ravaging the population. Today, these illnesses are all but eliminated here in the United States.

Chlorine certainly had a big part to play in this. Life Magazine even called chlorine “probably the most significant public health advance of the millennium.” But even decades later, scientists were not quite sure of exactly why. Research has suggested that chlorine reacts directly with biomolecules within the bacterial cell, denaturing pathogenic organisms. Further study put forward the idea that chlorine attacks enzymes, nucleic acids, and membrane lipids, among other targets, killing the pathogen as part of a “multiple hit” mechanism.

Types of Chlorine Disinfection

There are two main types of chlorine disinfection: chlorination and chloramine disinfection. Together, these two types of water treatment are used in the majority of disinfection and processing plants across the country. Let’s take a look at what these different types mean.


Typically, when we talk about chlorine water disinfection, we are talking about chlorination. This is simply the process of adding chlorine to the water supply, killing any parasites, bacteria, or viruses that may cause a public health issue. Safe chlorination involves adding up to four milligrams per liter (mg/L) to water — this may also be expressed as four parts per million (ppm). In most cases, this is enough to disinfect the water without putting humans, animals, or local ecosystems in danger.

Chlorination is nothing new. As far back as 1908, the authorities in Jersey City were using chlorine to disinfect the local water supply, reporting no harmful effects in the process. Over the next nine decades, this practice became common right across the country, with more than two-thirds of community water systems deploying this method by 1995 and almost all local water authorities by 1998.


Chloramine disinfection works in a similar way to chlorination — both use chlorine to kill and remove pathogens from the water supply. However, while chlorination utilizes an elemental chlorine molecule, chloramine is a little different. Chloramines use compounds from the chloramine group to kill and remove these pathogens. Usually, these compounds are monochloramine (one nitrogen and two hydrogen atoms bonded to one chlorine atom) or dichloramine (one nitrogen and one hydrogen atom bonded to two chlorine atoms).

When water is treated with chloramine, it remains safe for human consumption. Treated water is tested as non-toxic up to 50 mg/L or ppm, and the standard disinfection dose is not more than four mg/L or ppm. In other words, chloramine is effective in removing pathogens and will not cause a health or environmental hazard. Some local authorities will use chloramines almost exclusively, while others will use it temporarily while cleaning or maintaining water delivery pipework.

The Role of Sherwood Valves

As you might expect, Sherwood chlorine gas cylinder valves have an important part to play in these water treatment procedures. The precise role these valves play depends on the type of chlorine water treatment used.

Sherwood Valves and Chlorination

For municipal or large-scale water treatment centers, the role of Sherwood valves is pretty straightforward. These valves are used to apply gaseous chlorine molecules to the water en masse, directing jets of chlorine into the water supply and regulating the rate at which it dissolves.

As chlorine can be a toxic and hazardous gas if there are high levels of exposure, its usage is regulated by the Environmental Protection Agency or EPA. This necessitates a robust and reliable gas transit and handling system — from the storage canisters, via the pipework, through to the delivery nozzle. Sherwood valves sit within this system, ensuring safe and reliable operation from start to finish.

Not all water treatment processes will utilize gaseous chlorine. Smaller-scale treatment processes may use chlorine compounds that are added directly to the water. These dissolve and complete the chlorination process with no need for valves and associated systems. However, most municipal and larger-scale operations utilize gaseous chlorine.

Sherwood Valves and Chloramines

With chloramine treatment, the process is a little different. Chloramine may contain chlorine, but it is a different type of compound altogether and is not added to the water via a system featuring Sherwood’s chlorine cylinder valves. Instead, ammonia and chlorine are generally reacted together, generating chloramines. These chloramines are removed from the byproducts of the reaction and then added to the water.

But, of course, Sherwood cylinder valves still have a significant role to play here. The chlorine gas still needs to be delivered to the point of reaction with the ammonia, and this process still requires careful regulation and control. A specially designed system capable of handling chlorine gas, complete with specialized Sherwood chlorine gas cylinder valves, is a must during this phase of the chloramine treatment process.

Find Sherwood Chlorine Valves and Other Specialized Components at Chemtech

The Chemtech range is designed to provide the best solutions to our clients, and this includes the professional-quality components offered by Sherwood Valve. A leader in this space, Sherwood Valve provides highly reliable valves for a wide range of different applications. Browse our product pages and find what you need, or reach out to our team to learn more.