Is disinfection safe

The basic principle

Every effective disinfection method acts on living cells — that is how it works. So the question is not “is it harmful” but “when and under what conditions”.

The practical answer is simple: nobody may be in the room during treatment. After the treatment and proper airing, the room is safe to use.

That is why we always give a specific time for going back in rather than saying “after a while”. A vague time is the same as no time at all — people go back in whenever it suits them.

Two different questions: exposure and going back in

Most misunderstandings arise because two separate questions get mixed up. The first is about exposure during the treatment — what the concentration in the room would do while the equipment is running. The answer there is unambiguous: nobody may be present, and that is not over-caution.

The second is about going back in afterwards — the state of the room once the contact time has passed and it has been aired. The answer there is equally unambiguous in the other direction: the room is as usable as it was before the treatment.

That distinction also explains why the answer to “is it dangerous” is never simply yes or no. The process is what carries risk, not the result.

What makes ozone treatment risky

People search for this a lot, and there is a specific answer. Ozone is a strong oxidiser. That means it reacts chemically with whatever it meets and breaks molecules apart in the process — which is exactly why it acts on odour molecules and micro-organisms. That same property makes it an airway irritant at raised concentrations, because the lining of the airways is just another surface to react with.

In practice that means:

• during treatment, people, pets and house plants must not be in the room;
• after treatment the room stays closed for a set time and is then aired thoroughly;
• once the ozone has broken down it turns into ordinary oxygen and leaves no residue at all;
• which is exactly why nothing needs washing after ozone treatment.

Oxidation affects materials too. Prolonged high concentrations accelerate the ageing of rubber, some synthetics and natural latex — in practice that means fridge door seals, rubber hoses, some artificial-leather surfaces. So the intensity and duration of treatment are chosen according to the volume of the room and the task, not on a “more is better” basis. Fogging does not create this problem, but nor does it penetrate textiles as deeply.

Ozone treatment done correctly is safe. Done incorrectly, it is not. The difference is precisely in the airing and the time before going back in.

Children and sensitive groups

Sensitivity differs for three reasons, and those reasons determine what we do differently.

If any of these apply in your household, say so in your enquiry. It affects both the choice of method and the airing time we recommend. It is not a question of extra charges — it is information we need in order to do the job.

Practical advice for families with small children: after fogging, wipe the floor with clean water in the rooms where the child plays on the floor, and rinse any toys that were in the room. It is not formally required, but it costs ten minutes and settles the question.

If there is asthma or an allergy in the household

That changes two things. First the choice of method: if someone with airway sensitivity is regularly in the room, we more often choose surface treatment and ozone treatment with a longer airing period, rather than intensive fogging with a product whose smell lingers in textiles. Second the time before going back in: we recommend waiting considerably longer than the minimum and, if possible, returning the following day.

There is also another side to this that is only fair to state. We do not claim that treatment will improve respiratory symptoms or resolve an allergy — that would be a promise we cannot make. What we deal with is the condition of the building: damp, mould, the source of an odour, surfaces. If there are specific health concerns, those are a question for a doctor, not for a treatment company.

Pets

• All animals have to be taken out of the rooms being treated, including small animals in cages.
• An aquarium must be sealed and the air pump switched off — the pump draws room air and delivers it straight into the water, so a closed lid alone is not enough.
• Birds are more sensitive than other animals, because their respiratory system is more efficient and registers changes in the air faster. Take them out of the flat, not just out of the room.
• Reptiles in vivariums — like birds, they have to leave the home, and the heating equipment needs planning in advance.
• House plants are more sensitive than people. Damage shows up the next day as darkened leaf edges or wilting.
• After airing, animals can come back at the same time as people. Bedding and blankets that were in the room do not have to be washed after ozone treatment.

What exactly to prepare before we arrive is set out on the page how to prepare a property.