Allergens: Reducing Exposure

Controlling your family’s allergies could be easier than you might think. Learn how to reduce levels of allergens in your home.

Controlling Allergens

Controlling AllergensIf you have a definite allergy to one of the common allergens – dust mites, animal dander, mould spores or pollen – there are some steps that you can take to reduce your exposure to these allergens. This may help to reduce your symptoms.

There is a specific strategy for each of the common allergens.

House Dust Mites

House dust mites are the most frequent cause of allergies. They are microscopic animals that belong to the spider family. They eat discarded human skin cells (which are constantly shed from the body as dust), and they get their water from humidity in the atmosphere. They thrive in high humidity... and they reproduce very quickly.

Dust mites are found in mattresses, bedding, carpets, upholstery, old clothing, stuffed toys, and any other place where human skin cells accumulate. It is the dust mite’s droppings that cause allergic reactions. When disturbed, these tiny faecal particles become airborne, where they can be inhaled. However, dust mite allergens are heavier than other allergens, so they land and settle on surfaces relatively quickly, rather than staying airborne.

Controlling Dust Mites

  • Reduce household dust. Household dust contains all kinds of tiny particles – but much is made up of human skin cells. Dust also contains the droppings and dead bodies of dust mites. Damp-dust hard surfaces and floors regularly using cleaning products that are proven to remove mite allergens. Using a damp cloth or wipe (rather than a dry one) will help prevent the dust from becoming airborne.
  • Remove soft furnishings and clutter. This reduces places for dust to collect.
  • Replace carpets with linoleum or wooden floors. Hard surface flooring is easier to keep clean.
  • Replace fabric-covered seating. Choose leather or vinyl instead.
  • Reduce your home's humidity. Home humidity should ideally be below 50%. You can reduce humidity by avoiding damp conditions and increasing ventilation, for example by opening windows or trickle-vents, using extractor fans in bathrooms and kitchens and, if necessary, using a dehumidifier.

In the bedroom

  • Use allergen-proof bed covers. Encasing pillows, duvets and mattresses with impermeable covers (a complete bed-barrier system) stops the mites entering and reproducing.
  • Launder bedding weekly. Laundering all bedding that is not encased in a barrier cover, such as your sheets, blankets, pillowcases and duvet covers, on a hot wash (at least 55 ºC) will kill the dust mites.
  • Remove carpeting and other soft furnishings if possible. Better choices for bedroom flooring are wood, vinyl, linoleum or tiles. Also, consider removing upholstered furniture, non-washable curtains, and horizontal blinds (which collect dust) from the bedroom.
  • Buy washable soft toys. If you must have soft toys, keep them off the bed, and launder them every week on a hot wash (at least 55 ºC). Alternatively, place the toy in a plastic bag in the freezer to kill the mites, then launder the toy at the manufacturer’s recommended temperature.
  • Keep pets out of the bedroom.


Some plants (especially ones with colourful flowers) rely on insects to transport their pollen from plant to plant. But others – such as trees, weeds and grasses – release their pollen into the air to be carried by the wind. These airborne pollens are the usual cause of pollen allergy, also known as seasonal allergic rhinitis or hay fever.

Plants release pollen at certain times of the year, which is why pollen allergies are usually seasonal. Unlike some other allergens, pollen is very light – so it can travel long distances in the air. If you go outside or open a window during the pollen season ... you will be exposed to pollen.

Common Sources of Allergenic Pollen

  • Grasses: Most people who have hay fever in the UK are allergic to grass pollen. Rye grass and timothy grass are common causes.
  • Trees: Allergy to birch and oak tree pollen is common. Ash and cedar pollen can also trigger symptoms in some people.
  • Weeds: Weeds such as ragwort and other plants can also cause hay fever.

Avoiding Pollen

  • Stay indoors when pollen counts are high if possible. Pollen counts are generally higher on warm, dry days. Symptoms usually begin when the pollen count is over 50.
  • Avoid walking in grassy open spaces. Pollen counts rise in the early morning and evening, so it is particularly important to avoid grassy open spaces at these times.
  • Wear glasses or sunglasses. This will help stop pollen entering your eyes.
  • Consider wearing a face mask at peak pollen times. Covering your nose and mouth with a pollen-filtering mask will stop you inhaling pollen.
  • Keep windows and doors closed at peak pollen times. Pollen can easily enter your home through open windows and doors so it is best to keep them closed if you have a pollen allergy, especially in the evening and when grass is being cut.
  • Use air conditioning. If possible, use air-conditioning with a High Efficiency Particulate Air (HEPA) filter at home and in your car. Make sure your car’s air filter is changed at each service.
  • Avoid drying laundry outside when pollen counts are high. If necessary, tumble dry your laundry instead.
  • Damp-wipe surfaces regularly. Cleaning hard surfaces with a damp cloth or wipe using cleaning products that are proven to remove allergens, will collect the pollen that may have settled there and help stop it dispersing into the air.
  • Vacuum carpets and soft furnishings regularly. This will help to collect any pollen that has landed here.

Pet Allergens

In the UK, most pet allergies are caused by cats and dogs. Allergens from animals are found:

  • In their saliva (which can become airborne when dried)
  • In their sweat
  • In their urine
  • Coating their hair and skin cells (dander)
  • In their bedding or litter (from mice, gerbils, hamsters and guinea pigs)

Horses, cattle, rabbits, pet birds, and products made from feathers or down can also trigger allergy symptoms. Plus, you can suffer from pet allergy symptoms even if you do not have a pet, if you are exposed to pet allergens in other people's homes or on their clothes at work or school.

Controlling Pet Allergies

If your pet is the cause of your symptoms, removing them from your home is the most effective solution. You then need to take the following steps.

  • Vacuum all surfaces to remove pet hair.
  • Damp-wipe household surfaces and floors using products that are proven to remove pet allergens.
  • Steam-clean carpets and upholstery.
  • Launder all bedding and curtains.

If it is not possible to remove your pet from your home, you may find the following measures helpful.

  • Keep your pet outside, if possible. You will reduce pet allergens in your home if you have the type of pet that can live outside.
  • Limit the pet's contact with soft furnishings. If the pet has to be indoors, try to keep it in a room without carpets and with fewer soft furnishings. Provide the pet with a comfortable bed of its own, and never let the pet into the allergic person's bedroom.
  • Regularly vacuum carpets, mattresses and upholstery.
  • Launder all bedding and soft furnishings on which an animal has laid.
  • Regularly damp-wipe surfaces and floors using cleaning products that are proven to remove pet allergens.

Change clothes after attending pets (e.g. horses) before entering the home of the allergic person.

Mould Spores

Moulds are microscopic members of the fungus family. They grow both indoors and out, preferring damp, warm environments. When moulds grow in large quantities, called ‘colonies’, they can be seen with the naked eye.

Mould releases tiny seeds, called ‘spores’ that are carried through the air. When these spores are breathed in they can cause allergic reactions.

  • Outdoor Moulds: Found on rotting logs, fallen leaves, compost piles, grasses/grains, and dead plants. They are particularly common in the autumn months.
  • Indoor Moulds: Found growing on decaying food, and in damp areas, such as in the bathroom or kitchen. They thrive in damp patches on walls and around window frames (especially where there is condensation).

Avoiding Mold Spores

  • Avoid moulds outdoors. Do not walk in woods in mild damp conditions, or among rotting leaves. Avoid damp or musty buildings or places where hay or grain is stored. Avoid cutting grass, raking leaves, turning compost heaps, and being outside when harvesting is in progress. If you must do these things, consider wearing a face-mask.
  • Keep your home dry and well-ventilated. Repair any indoor water damage promptly, e.g. by fixing guttering and leaks. Open your windows, use extractor fans and avoid drying laundry indoors.
  • Use a dehumidifier if necessary. A dehumidifier should only be needed if relative humidity is constantly high (above 50 %). You will need to empty and clean the reservoir regularly to stop mould growing in it.
  • Remove visible mould growth promptly from surfaces. Use suitable disinfectant cleaning products that are proven to kill moulds.
  • Regularly clean problem areas, such as refrigerator door seals and shower curtains.
  • Replace carpets with hard flooring and wallpaper with paint.
  • Keep houseplants to a minimum and change the soil regularly.
  • Keep household surfaces as dry as possible.