Indoor air can be up to 3.5 times worse than outdoor air and can lead to lung diseases, heart disease, and even cancer.

Air purifiers can help reduce illness by sanitising the air and preventing you from breathing in pollutants.

Here’s everything you need to know about air purifiers including how they work, the different types of air purifiers, and how to choose the right one to suit you.

Air Purifiers for Hire

What does an air purifier do?

An air purifier does exactly what it says, it purifies the air. It filters dust, pollen, odours, bacteria, and in many cases larger matter such as pet hair.

It then releases the filtered air into your room and prevents you from breathing in these pollutants which can help to reduce infections.


How does an air purifier work?

Air flows towards the machine and goes through a filter which removes harmful matter. It then pushes the filtered air out.

Many work with a vacuum which removes larger particles such as pet hair. Air purifiers not only filter the air but sanitise it too.


What is the difference between an air purifier and an air scrubber?

Air purifiers or air cleaners, clean airborne particles but an air scrubber removes particles from the air and surrounding surfaces.

Air scrubbers are designed for construction or industrial environments because they can take out metallic and wooden particles as well as the bacteria and dust an air purifier can absorb.

An air scrubber may be used as a name for an air purifier, but they are different.

air purifier in a dentist

Types of air purifiers

There are several different types of air purifiers which work in slightly different ways with varying degrees of effectiveness.



Otherwise known as High Efficiency Particulate Air filters. These can trap mould, bacteria, dust, and can even trap viruses.

They don’t, however, remove odours, chemicals, or gases, which is why they are usually paired with activated carbon which does absorb these.

The HEPA filter is a mesh made of plastic threads that is folded to create different sized gaps to trap different sizes of particles.

HEPA filters have to meet a certain standard by trapping over 99% of particles larger than 0.3 microns.

The HEPA filter works in three different ways. Firstly, air is pushed through a large surface area.

Then the inertia effect means the larger particles hit the fibre and stick to it. Then comes the blocking effect where smaller particles with a lower mass move around the obstacle (the fibre) but if they move close to the fibre, they’re attracted to it and they also stick.

The final stage is the diffusion effect where, as per the Brownian motion, the smallest particles collide with other gas molecules and change direction. They then stick to the filter as soon as they touch it.


Activated carbon

Activated carbon is used with HEPA filters because it traps odours, gases, and other chemicals. It also absorbs formaldehyde which can be found in carpet and furniture upholstery. Even perfumes from cleaning chemicals can be removed by activated carbon.

The carbon is made from lots of molecular sized pores that are highly absorbent and have chemical bonding.

Once used in gas masks and to purify water, it is now used to clean air.

The activated carbon works by binding gaseous impurities by adhesion. One gram of it has an area of 1000 square metres.



UV or Ultraviolet is in the form of a lamp which is used with air purifiers. It can kill germs but it’s not particularly good at getting rid of airborne particles.

It works by letting microorganisms pass by the UV rays which creates cellular damage that turns the microorganism into water and carbon dioxide.


Negative ion

Negative ions are oxygen atoms that gain an electron. They magnetically attract airborne particles. The particles drop and attach to surroundings such as walls, windows, or other items in the room.

This is less effective than other air purifiers as it isn’t actually cleaning the air. The particles can always come undone and contaminate the air again.



There is debate about whether this type of air purifier is safe to use as it may make asthma symptoms flare up, which is the opposite of what you want to happen when using an air purifier.

It works by producing gas ozone that react to chemicals, but this can take months or years and it doesn’t remove dust or pollen.

It is usually used in conjunction with a negative ion, but it is still not an effective way of purifying the air.


How much electricity does an air purifier use?

When purchasing an air purifier, it’s not only the rental hire cost that you need to consider, but how much they cost to run.

Air purifiers don’t use a lot of electric. They use on average 47.9kWh to 769.88kWh per year.

Or in pricing terms, around 10p to 30p a day which could be around £70 a year. Compared with the cost of sick pay in the workplace, this is a good investment.


Why does air need to be purified?

We all know that outside air is polluted from vehicles, manufacturing, and even pollen from plants. But indoor air can be worse.

On average indoor air pollution is 3.5 times higher than outdoor air pollution.

Indoor air can contain dirt, dust mites, or gases such as carbon monoxide or sulphur dioxide.

These can be harmful for us to breathe and can lead to lung diseases. Household air can be so harmful, that it is responsible for an estimated 3.2 million deaths per year. It can also lead to noncommunicable diseases such as strokes, heart disease, and even cancer.

The reduction of these air pollutants with an air purifier can help to reduce symptoms in certain cases and prevent disease progression.

How to use an air purifier

Air should be cleaned three times an hour to be able to be effective against allergens.

All Kärcher’s air purifiers work in a similar way. They are extremely easy to use, so you won’t even need to read the manual.

  1. Simply plug it in
  2. Touch the button on top and the LED screen at the side will light up to show the level of air pollution and the remaining lifetime of the filter.
  3. Enjoy clean indoor air.


How long does an air purifier take to work?

An air purifier takes minutes to clean the air.

The AF 100 air purifier takes just under five minutes to clear a smoke-filled room, which you can watch here.

A study also found that the benefits of air purifiers were detectable within 48 hours by reducing inflammation which can impact blood pressure.


Air purifiers and Covid

Air purifiers have been found to remove Covid from the air.

Addenbrooke’s Hospital and the University of Cambridge carried out an experiment and placed an air filtration machine in Covid-19 wards.

They found, without the machine, there was Covid still in the room. But with the machine, the air purifier removed almost all traces of airborne SARS-CoV-2.

Not only did the air cleaner remove Covid but it significantly reduced the levels of bacterial, fungal, and other bioaerosols.


Air purifiers and allergies

Allergens trigger an immune response from you which can cause anything from sneezing, coughing, to difficulty breathing.

Air purifiers can trap airborne allergens to make it more comfortable for you and hopefully eradicate any allergic response.

If you are using an air purifier in your home to help with pet dander, it is also best to wash your pet often to get rid of excess fur and skin which cause the allergic reaction.


Air purifiers and mould

Air purifiers can help sanitise the air to prevent you from breathing in spores from damp and mould which can cause breathing problems.

Air purifiers can also reduce the humidity levels from the air which can make the environment more comfortable.


Types of filters for air purifiers

It is important to choose the right filter for your air purifier to ensure it is removing what you need from the air.

The HEPA 13 filter absorbs 99.95% of suspended matter whereas the HEPA 14 absorbs over 99.995%.

The HEPA 14 can remove the smallest of particles including SARS-CoV-2 (Covid-19).

The HEPA 14 can remove viruses, bacteria, fungi, and germs. Kärcher have combined this filter with high performance products to create greater safety for your workplace.


How often do you change your air filter?

Cleaning is not recommended because water will not work properly to remove contaminates, and filters will lose their effectiveness over time by catching all your indoor pollutants.

It is best to replace your filter every three months or if you are in an environment which needs to have the highest of hygiene standards, then every month.


The benefits of air purifiers

  • Reduce illness

Air purifiers have the potential to reduce people’s exposure to air pollutants which can help reduce illness.

It has been proven that air purifiers even remove Covid.


  • Improve sleep quality

Although more research is needed, it seems air purifiers may improve sleep quality, possibly because of reducing humidity and stuffiness of air.


  • Reduce humidity levels

Air purifiers take dampness out of the air to reduce humidity levels making it more comfortable in the workplace or at home.


  • Prevents odours

Air purifiers also take odours out of the air. In workplaces were there may be a lot of different smells, an air purifier quickly removes these.


  • Increase productivity

Air quality can significantly impact an employees’ cognitive function, response times, focus, and productivity as stated by a recent Harvard study.


How to choose the right of air purifier for you


If the rooms you are using the air purifier in are large, you may need more than one air cleaner.

The AF 100 can be used in a room of up to 100 metres squared. You should measure your room beforehand to choose the appropriate amount of air purifiers to be most effective.



Generally, air purifiers aren’t particularly loud, but you will want to make sure if you are using it for a school or hotel room that it is quiet enough not to disturb the occupants.

The workplace ordinance states that noises can’t be above 50 dB.



The type of air purifier you need will depend on your environment. If you are at home and want to remove allergens such as pollen or pet dander, then you need a HEPA filter.

If you are in a work environment where there is a lot of odours, like in hospitality then you will need a HEPA filter with activated carbon.

Over 93,000 workers believe they caught Covid at work, so if you want to reduce this, then a HEPA 14 filter can get rid of these small particles.



Your budget is of course a deciding factor when deciding on air cleaner hire. By renting an air purifier, you can get exactly what you need but for a fraction of the cost.

Cash flow is always a worry for businesses, and Karcher Hire offers both short and long-term contracts, so you only have to pay for as long as you need the air purifier or as long as you can afford it.


Other ways to reduce indoor pollutants

While using an air purifier will help to remove indoor air pollution, it is best to also try and remove the pollution as much as possible from the source.

It is also advisable to take other precautions to help reduce pollutants such as:

  • Clean textiles

Fabric and rugs should be cleaned regularly so they don’t trap pollutants.

  • Wash pets

Pets shed hair and skin which can cause allergies. Washing them regularly helps to remove this.

  • Ventilate

Ventilation is always important for your home or workplace. It removes damp from the air to prevent mould and circulates fresh air.

  • Change your air filters

Air filters will get clogged with the pollutants they are removing from the air. If your air filter is clogged it will not work efficiently.


Hiring an air purifier is a great way to help you reduce illness in your workplace and reduce your costs.

Air purifier hire means you get the latest models without having to sacrifice your cashflow.


View our range of air purifiers available to hire today.


We pride ourselves on being able to offer the following to all our valued customers:

– Next Day Delivery anywhere in the UK (subject to location & availability)
– Free site visits and advice, ensuring you hire the right machine for the application
– Flexible hire periods, from 2 days to 5 years
– Maintenance included as standard
– Full training on delivery of your equipment
– Quality, modern fleet, maintained to ISO9001:2008 standards
– Breakdown response

With a fleet of equipment growing daily, we’re ready to take your hire. Call us on 0345 222 8000 or fill out a simple enquiry form.

Clean Sweep Hire Trading As Kärcher Hire

Company Registration Number: 06523042

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