What Happens When You Mix Bleach and Ammonia?

by Kate Onissiphorou

Mixing bleach and ammonia creates a highly toxic gas called chloramine that can potentially kill anyone who inhales it. You should therefore never mix these two cleaning agents.

Many household cleaning products contain bleach or ammonia, meaning they’re already dangerous in themselves. However, these chemicals can become even more lethal if they mix. That’s because the reaction between bleach and ammonia produces one of two types of toxic gases, depending on whether the bleach is peroxide or chlorine-based. As the reaction is also highly exothermic, it can potentially cause explosions if the area isn’t ventilated.

You should always separate bleach and ammonia containers and never use them in tandem or successively when cleaning surfaces. Only use one of these chemicals at a time, and rinse off the surfaces with water afterwards. Even trace amounts of these chemicals combining can be very dangerous.

Can mixing bleach and ammonia kill you?

The short answer is definitely YES. Mixing bleach and ammonia is a definitely bad idea if you want to stay healthy and alive. 

There are two main types of toxic products that can be produced by mixing bleach and ammonia. This depends on the active ingredient of the bleach. As we explain below, a bleach product can either be chlorine-based or peroxide-based.

Chlorine-based bleach

Most bleach used in laundry and household cleaning products contain 3% to 6% sodium hypochlorite (NaOCl) as the active ingredient.

 Three different coloured plastic bottles of bleachThey may also include other chemicals, such as sodium hydroxide, hydrogen peroxide, and calcium hypochlorite, but only in trace amounts. 

Chlorine-based bleach products are designed to remove stains and kill bacteria through oxidation reactions. They remove colours by changing the chemical structure of the chromophores or the parts of molecules that reflect or refract visible light, thereby creating the appearance of colours.

When sodium hypochlorite is mixed with ammonia, chloramine gas is produced. The gas can damage your airways and potentially kill you.

Peroxide-based bleach

Peroxide-based bleach products use oxygen as the active oxidising agent, as opposed to chlorine. 

The three classes of this type of bleach are hydrogen peroxide (H2H2), sodium percarbonate (Na2H3CO6), and sodium perborate (Na2H4B2O8). Mixing a peroxide-based bleach with ammonia violently releases the oxygen in the bleach. This is a highly exothermic and potentially explosive reaction.

The chemical reaction of bleach and ammonia 

The most dangerous and potentially lethal gas byproduct of the reaction between sodium hypochlorite and ammonia is chloramine, which has the chemical formula NH2Cl. 

The reaction is highly exothermic and evolves chloramine gas. The balanced chemical equation is shown below.

2 NaOCl + NH3 NaCl + NaOH + NH2Cl

Symptoms of bleach and ammonia exposure

Exposure to the by-product of the chemical reaction of bleach and ammonia can be a serious medical emergency, depending on the amount of gas that’s inhaled. A 3D rendering of the human respiratory system

Inhaling chloramine gas directly affects the respiratory system, causing a variety of harmful symptoms. These include:

  • Coughing – this is an immediate reflex reaction as the linings of air passage are irritated
  • Nausea – this may also immediately occur as the nervous system is affected
  • Shortness of breath – the patient may start gasping for air as the diaphragm reacts to expel the noxious gas
  • Watery eyes – chloramine is an oxidising agent that can irritate your eyes 
  • Chest pain – this may occur as the lungs and heart start to become fatigued
  • Pneumonia and fluid build-up in the lungs – this defence reaction of the body can lead to death as the oxygen supply to the brain becomes depleted.

How to safely handle bleach and ammonia

To prevent the accidental mixing of ammonia and bleach, it would be better to simply just buy one of these two cleaning agents. However, if you do need both, take care to properly label each product and affix a large warning to both containers. A vector illustration of the caution ammonia sign

It’s also a good idea to store the products separately and only use each one in a designated area. For example, you might choose to only use bleach in the bathroom to clean the toilet bowl.

After using bleach or ammonia, always rinse the surface with running water. Be sure to dilute each product and never use them in succession or apply them with the same mop. And of course, always use protective equipment, such as gloves and an apron – or even a mask and goggles – when handling any toxic chemical.

What to do if you think you’ve been exposed to bleach and ammonia

If you think you may have been exposed to the toxic gas generated by the reaction between bleach and ammonia, immediately vacate the contaminated area. Woman cleaning a kitchen worktop with a spray detergent

Only breathe in fresh air from an open area away from the affected area. Remove any exposed clothing and rinse any body part that’s been in contact with the chemicals. If symptoms become worse, call an ambulance.


Bleach and ammonia in themselves are already very dangerous. When combined, they become even more toxic as they produce a potentially deadly gas called chloramine. You should never mix these two cleaning agents. If you do need to use both agents, never apply them in succession, even when diluted, and always wear PPE.

You can buy a range of high-quality ammonia solutions from our online shop. Visit our website or speak to a member of our friendly and experienced team to find out more.


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