Almost every foam product has a distinct odour when first unpacked, and it worries people who were not expecting it. It is normal, temporary and worth understanding rather than ignoring.

What Causes It

Polyurethane foam is produced through a chemical reaction, and small quantities of volatile organic compounds remain in the material afterwards.

Vacuum packing seals those in. When the packaging is opened, they release over a period as the foam expands and air circulates through it. This is generally referred to as off-gassing.

How Long It Lasts

• Strongest in the first few hours after unpacking
• Noticeably reduced within two or three days
• Usually gone within a week in a ventilated room
• Longer in a cold or unventilated space
• Longer for large dense pieces than small ones

The timeline broadly matches the expansion window, which is convenient: ranges stating two to three days for foam to reach full size, as at hobestluk.net, are describing roughly the same period during which the smell fades.

Speeding It Up

Ventilation is the whole answer. Open a window, leave the piece uncovered, and give it space on all sides rather than pushing it against a wall.

Warmth helps, since it accelerates release. A cool room slows both the expansion and the airing.

Avoid covering it with throws or cushions for the first day or two, which traps the odour in the material.

Where to Unpack It

Ideally in the room where it will live, since it becomes considerably harder to move once expanded.

Where somebody in the household is particularly sensitive, unpacking in a spare room or a garage for the first day and moving it afterwards is a reasonable compromise. Moving expanded foam is awkward rather than heavy.

Is It Harmful

Emissions from new furniture are regulated in many markets, and reputable manufacturers test against those standards.

Some people find the smell unpleasant and some report headaches during the first day. That is a reasonable reason to ventilate thoroughly rather than a reason for alarm.

Anyone with asthma or a respiratory condition, and households with babies, may prefer to air a piece in a separate room before it enters a bedroom or living space. Where symptoms occur or persist, that is a matter for a GP rather than something to push through.

If It Does Not Fade

A smell still strong after a couple of weeks in a ventilated room is not typical and is worth raising with the seller within the return period.

The same applies to any smell that is chemical rather than simply new, or that provokes a reaction in the household.

Covers Help

Where the cover removes, washing it before first use removes any odour in the fabric and leaves only the foam to air.

That is worth doing anyway, since covers pick up dust in packaging and warehousing.