How Long Does It Take for Formaldehyde to Off-gas?


The indoor air quality (IAQ) of your home, office, and school is getting polluted by various formaldehyde gas sources. These sources include pressed-wood products, foam installation, wallpaper, paints, cosmetics, and many other household products. 

Formaldehyde is colorless and flammable at room temperature but has a strong odor. It is used in the manufacturing process, and it is a part of VOCs (Volatile organic compounds).

The release of formaldehyde from the products after manufacturing is known as off-gassing, but the main question is – how long does it take for formaldehyde to off-gas? On average, it takes at least two years for some formaldehyde to off-gas enough in a newly built or newly renovated home for it to be comparable to formaldehyde levels of an already “lived in” home. Even then, it’s still only a partial off-gassing, but it’s enough to become bearable for most people. Beyond that, it could take over 10 years for most of the formaldehyde to disappear.

There are many factors that affect the rate of off-gassing and not every home is the same, so consider this answer more as a general estimation.

For example, a lot will depend on where formaldehyde was used. Some more porous parts of your home will take just a few months to off-gas (like paint or mattress), while more solid, pressed materials (like furniture and flooring) could take years.


Formaldehyde – What It Is

Formaldehyde is a colorless gas with a pungent smell mostly used to make building material and many other household products. Formaldehyde breaks down into the air very quickly, generally within the hours. It also gets dissolved in water very easily but doesn’t long last in it.

Formaldehyde becomes formalin when it is dissolved in water and is used as an industrial disinfectant. Moreover, it is used as a preservative in funeral homes and medical labs. It is also used as a preservative in food and daily household products like cleaning products and cosmetics.

Living organisms also produce formaldehyde as part of their normal metabolic process.


Indoor and outdoor Levels of Formaldehyde

Indoor air contains higher levels of formaldehyde as compared to outdoor air. Indoor air usually contains about 0.02-4 million (ppm) while outdoor air only contains 0.001-0.02 ppm concentration in urban areas, which is even less in the rural areas.

According to ATSDR (Agency for Toxic Substances & Disease Registry), there are observable breathing symptoms in air contaminated with formaldehyde. 

  • If the formaldehyde level is from 0.1 to 0.5 ppm, it can cause nasal and eye irritation, increase the risk of asthma/allergies and cause neurological effects.
  • If the level is 0.6 to 1.9 ppm, it will cause eczema and changes in lung function
  • A high level of exposure to an environment containing formaldehyde can cause some types of cancer.


Sources of Formaldehyde in Your Home

Formaldehyde can be found in almost every corner of your home and used in manufacturing various household products. Therefore, the process of off-gassing can occur anywhere in the house, and to be aware of these household products, the following is a list of products that might be giving off formaldehyde.


Formaldehyde in the Bedroom

A bedroom is a place to relax, but it contains several products that are a potential source of off-gassing.

  • Walls and Floor: Formaldehyde is present in the paint on the walls and the adhesive on the floor beneath the carpet.
  • Bed, Nightstand, and Dresser: If the furniture in the bedroom is made up of pressed-wood products like plywood and fiberboard, then it is a chance that formaldehyde might have been used in its manufacturing.


Formaldehyde in the Bathroom

Bathrooms seem to be the most unlikely place for manufacturing chemicals but can be found in many products.

  • Shampoo and Body Wash: Formaldehyde is used as a preservative and anti-bacterial agent in many soaps and shampoos. This chemical is used to make your shampoo stable for more than a week, but it is a harmful chemical used to wash up.
  • Cosmetics and Personal Care Products: Makeup products like nail polish, hairspray, and styling balm may have formaldehyde in them. While sitting in your cabin, these beauty products can release the chemical in the form of gas into the air.


Formaldehyde in the Kitchen

Kitchens are usually breeding grounds for harmful bacteria and mold. Similarly, they could contain formaldehyde as it can come with many products. Usually, no new furniture goes into the kitchen, and the old furniture becomes formaldehyde-free over time.

But in new homes where air movement is less can cause formaldehyde to remain for a longer time.

  • Gas Stove: Gas stoves emit formaldehyde naturally along with carbon monoxide and nitrogen dioxide. Therefore, it is essential to use an exhaust fan while cooking.
  • Paper Towels and Grocery Bags: Grocery bags and paper towels inside your pantry can also be a reason for formaldehyde off-gassing. You can replace the bags and paper towels with reusable products.


Formaldehyde in the Living Room

The living room is usually a place in your house filled with furniture, which means that this room has more formaldehyde exposure than any other area in the home. Improving the air circulation in the house can help in improving the air quality of the house.

  • Sofas, Side Tables, and Coffee Tables: If the furniture is pressed-wood, has varnish on it, or the fabric of your couches or chairs is synthetic, then there is a chance that there is some formaldehyde in the air of your living room.
  • Candles and Air Fresheners: Candles and air fresheners used to make your home smell better also contain formaldehyde. When you spray or burn them, you are intentionally releasing the formaldehyde gas into the air.


Health Effects of Formaldehyde Off-gassing

Exposure to formaldehyde can cause various health problems, and their severity depends upon the duration and concentration of formaldehyde exposure. Some people can be more sensitive to formaldehyde and show early symptoms than other people.

Symptoms of short-term exposure to formaldehyde can include irritation in the eyes, nose, and throat. Moreover, coughing, headaches, dizziness, and nausea are other symptoms found in people. On the other hand, long-term exposure to formaldehyde can cause some cancer.


How Can I Reduce Formaldehyde Levels and Speed Up Its Off-Gassing?

Knowing that formaldehyde can have harmful effects on your health and can be found anywhere in the house can be scary. However, if you know how you can reduce formaldehyde levels in the air, it might help you keep your family safe.

  • Reduce Consumption of Tobacco: Smoke that comes out of tobacco products can increase formaldehyde concentration in the air. Therefore, consumption of tobacco inside the house should be reduced.
  • Improve Indoor Ventilation: If your house’s indoor ventilation is adequate, it will help reduce the level of formaldehyde concentration. You can improve the ventilation by opening windows of different rooms and allowing fresh air to cross.
  • Allow New Products to Off-gas: After purchasing new furniture, you should keep it outside of your living space to release the gases.
  • Control Indoor Humidity level: Keeping your house’s humidity level low can help you control the formaldehyde off-gassing as in the high and humid temperature formaldehyde release very quickly.
  • Wash Clothes Before Wearing: Most manufacturers use chemicals like formaldehyde to keep the fabric from shrinking and wrinkling. Therefore, washing the clothes before wearing can remove the substances to contact your skin.
  • Purchase Products with Low or No formaldehyde: The best way to protect yourself from formaldehyde is through prevention. It is better to bring less formaldehyde in your house by purchasing internationally known products for not using formaldehyde.
  • Use Exhaust Fan While Cooking: Using an exhaust fan while cooking will dilute the formaldehyde released in the air from gas stoves while cooking.
  • Keep Your Fireplace Clean: Burning wood inside the house will expose you to formaldehyde, and therefore, proper cleaning and ventilation are required so that the chemicals can get out of your home.


Related Questions

How can I speed up off-gassing?

The new furniture and new paints in the house give a pungent smell. That is because of the higher VOC off-gassing rate, which eventually minimizes, and the smell disappears. As most of the time is spent inside the house, it is essential to live in the clean air so that our health may not harm.

We can use the ventilation and heating method because formaldehyde releases quickly, making the process fast in high temperatures.


What is an acceptable level of formaldehyde?

Indoor formaldehyde levels should be as low as possible, but they will still be higher than the outdoor formaldehyde level. The average outdoor formaldehyde level should be about 2.0 ppb, and the indoor intermediate formaldehyde level should be about 20 ppb. Similarly, the average level in the material used for house manufacturing is 40 ppb.


Will off-gassing of new purchase products make me sick?

It depends upon the product being used and the VOC it releases. Some products do their highest off-gassing for about a month after manufacturing, and other products may continue off-gassing for years. There are ways through which the process of off-gassing can be increased, and adverse health effects can be minimized.