How does bleach work? And is bleach a disinfectant? Your questions answered

Keeping your home clean is important, but so is ensuring the safety of you and your household. Bleach is a common household cleaning product, but do you know how to use bleach safely? This guide aims to answer all your bleach-related questions, including ‘how does bleach work’ and ‘how long does bleach last’.

What is chlorine bleach?

Bleach used in household cleaning products is called chlorine bleach, also known as sodium hypochlorite. What you actually get when you buy household bleach is a mix of sodium hypochlorite and water, usually in a 5.25% solution. Chlorine bleach is a strong oxidising agent and can be hazardous if not used properly. However, when you know exactly how to use it, and most importantly, how to use it safely, it can be a great household cleaner suitable for sanitising many surfaces. If you’re wondering how to clean with bleach, start with trusted brands like Domestos. Their specially designed bottles make it easier to get into all the nooks and crannies.

What is non-chlorine bleach?

Non-chlorine bleaches are sometimes called ‘colour-safe bleach’ as, you guessed it, they are safe to use without the risk of colour running from clothing and other items. An example of a good chlorine-free bleach is Seventh Generation, which uses a biodegradable formula with hydrogen peroxide to fight tough stains and is made with no harsh smell, fragrances, or dyes.

Chlorine vs bleach

The battle of chlorine vs bleach isn’t really a battle at all. This is because chlorine is a a chemical element often found in bleach, though, as explained above, it’s possible to purchase non-chlorine bleach (though, if you’re wondering which is best for your pool, the answer is ALWAYS chlorine – DO NOT put bleach in your pool water!).

How does bleach work and is bleach a disinfectant?

So, now you know what bleach is, how does bleach work? Well, the sodium hypochlorite in the bleach oxidises molecules in the cells of the germs it meets. This process eradicates bacteria and viruses to protect you from illness.

This helps answer the question, ‘is bleach a disinfectant?’ (the answer is yes). Bleach contains chemicals called oxidative agents which cause oxidisation when they come into contact with germs or stains and this kills germs. Check out this article on how to disinfect your house for more cleaning tips.

How long does bleach take to work and how much bleach is needed to sanitize?

So, you know how bleach works, but how long does bleach take to work? In general, bleach solutions take around 10 minutes of full-contact time to complete disinfection. This is why bleach can be less effective on smaller objects, such as phones and door handles, as the bleach evaporates quickly. If you find the bleach has evaporated too quickly, you may need to use a little bit more, though it is always important to read the instructions.

How to use bleach safely

If you’re asking yourself ‘Is bleach a good disinfectant to use around the home?’, the answer is yes, but only if you know how to safely use bleach.

How to safely clean with bleach:

• Be sure to measure out the recommended dosage (see below).

• Carefully follow the instructions on the product’s label.

• Test on a small area of the surface first to check the material will not be damaged.

• Wear rubber gloves to prevent contact with skin.

• Wear eye protection – if you do get bleach in your eye, rinse immediately and call your doctor.

• Ventilate the room by opening the windows or using a fan.

• Keep children and pets out of the room.

• Only use chlorine bleach in fairly low concentrations – typically 5.25% or 6% sodium hypochlorite.

• Do not mix bleach with ammonia or any other cleaning product.

It’s not just when using bleach that you should be careful, but also when you’re storing it. Bleach and other household cleaning products should always be stored out of reach of little hands and paws and always out of direct sunlight. For more household cleaning product storage tips, check out this handy product storage tips guide.

How to safely clean with bleach

Remember, when using bleach to clean, always follow the above safety instructions. Below we’ve listed several uses of bleach and how to perform household cleaning with bleach.

How to clean bathroom tiles with bleach

Tile grout is notorious for getting grubby, and a build-up of soap scum, limescale, and mould can make your bathroom look dirtier than it actually is.

1. Mix equal parts of chlorine bleach and water in a spray bottle and spray the grout.

2. Alternatively, mix the solution in a basin and use a sponge to apply to the grout. 

3. Allow the diluted chlorine bleach to get to work for approximately 15 minutes, then scrub with a stiff brush or old toothbrush.

4. You should only use chlorine bleach if you have white tiles and grout – the bleach will have a whitening effect – not so desirable if you have dark tile grout and tiles!

For more tips on cleaning bathroom tiles, read our extensive guide.

Cleaning shower curtains with bleach

Banish mould and mildew from your shower curtains with the help of some chlorine bleach!

1. Check that your shower curtains are machine-washable, then pop them in the washing machine and wash in warm water with your normal dose of detergent and ½ cup of chlorine bleach (approx. 120ml).

2. Allow to air dry or place in the tumble dryer on the lowest setting.

3. Always consult the care label for specific advice on the temperature and setting to use when washing and drying your shower curtains.

Want to know more about cleaning shower curtains? Check our in depth guide.

Worktops and other surfaces

Chlorine bleach is great for disinfecting a variety of surfaces, for example food preparation areas in the kitchen such as worktops and chopping boards, and toilets and sinks in the bathroom. It’s also very effective at sanitising surfaces in the home, such as door handles, to prevent the spread of germs when someone is ill.

To clean and disinfect your surfaces, wash them with hot, soapy water first, then rinse, and disinfect by applying a mixture of 1 tablespoon of chlorine bleach per 4.5 litres of water, preferably using a spray bottle and clean cloth. Allow to air-dry to prevent re-contaminating the surface by drying with a towel.

Disinfecting rubbish bins

As we’ve seen when answering the question ‘is bleach a disinfectant?’ bleach is a great way to clean and sanitize around the home and this includes bins! Bleach is strong enough to deal with the nasty dirt that builds up in bins. Mix bleach cleaner with dishwashing liquid, dilute with water, then clean out the insides with this solution.

Use biocides safely. Always read the label and product information before use.

Sterilising second-hand items

If you’ve bought something that’s been used before, make sure to disinfect it with household bleach. Just drop a tiny bit into a water solution, soak the item and rinse. This will ensure any bacteria are removed immediately – it doesn’t take long at all!

White porcelain

If you’re trying to give white porcelain items that extra sparkle, put some bleach on a paper towel and wipe over the surface. Rinse thoroughly and dry with a clean cloth.

How long does bleach last?

In terms of shelf life, bleach lasts for about six months before it starts to degrade.

In terms of treatment, this really depends on what you’re cleaning and what it’s been subjected to. A very dirty bathroom may need a deep clean with bleach and then regular treatment with the rest of the bathroom cleaning, and a bathroom that’s used by a lot of people will need daily treatment.