In brief
- 01Lower class, lower formaldehyde, but the limits depend on the standard.
- 02IS 303:2024 defines E1 and E2 for plywood; E0 comes from other systems.
- 03Ask which standard and test method any emission label refers to.
E0, E1 and E2 are labels for how much formaldehyde a plywood or board product gives off, with a lower number meaning lower emissions. The catch is that the limits behind each label depend on the standard and the test method. In India, IS 303:2024 defines E1 and E2 classes for plywood; E0 is not one of its classes.
Where does formaldehyde in plywood come from?
Most plywood is bonded with resins built on formaldehyde, such as urea-formaldehyde, melamine-urea-formaldehyde and phenol-formaldehyde. Formaldehyde that has not fully reacted, or that is released as the resin ages, escapes slowly as a gas. Wood itself contains small natural amounts too. Release is accelerated by heat and, to a lesser degree, by humidity.
Why it matters indoors
Formaldehyde can irritate the eyes, nose, throat and skin, and the International Agency for Research on Cancer classifies it as carcinogenic to humans. A fitted kitchen or a wall of wardrobes can put many square metres of board into one room, and rooms that stay closed and air-conditioned for long hours exchange less air. The emission class of the core deserves the same attention as the finish on top.
What do E1 and E2 mean in the Indian standards?
IS 303:2024 (general-purpose plywood) and IS 710:2024 (marine plywood) both measure formaldehyde content with the perforator method of IS 13745, which extracts formaldehyde from an oven-dried sample of the board. The classes are:
| Class | Formaldehyde content | Test method |
|---|---|---|
| E1 | Below 8 mg per 100 g of oven-dry board | Perforator, IS 13745 |
| E2 | Above 8 and below 30 mg per 100 g | Perforator, IS 13745 |
Both standards also include an optional steady-state emission test in a chamber, to IS/ISO 12460-1, which measures what a board actually releases into the air under controlled conditions. IS 710:2024 draws its line for that test at 0.124 mg/m³. Licences under IS 303:2024 are granted for a declared formaldehyde class, and IS 710:2024 requires the class to be marked on each board.
So where does E0 come from?
From other systems. In the Australian and New Zealand plywood scheme, emissions are measured with a desiccator test in milligrams per litre: E0 means 0.5 mg/L or less and E1 means 1.0 mg/L or less. The European Union measures emissions in a chamber in mg/m³, and from 6 August 2026 an EU-wide limit of 0.062 mg/m³ applies to wood-based materials and furniture. The United States sets 0.05 ppm for hardwood plywood under its TSCA Title VI rules.
| System | How it is measured | Units | Example figure |
|---|---|---|---|
| India: IS 303 and IS 710 | Perforator (content in the board) | mg/100 g | E1: below 8 |
| India: optional test | Chamber (release into air) | mg/m³ | IS 710 line: 0.124 |
| Australia and New Zealand | Desiccator | mg/L | E0: 0.5 or less; E1: 1.0 or less |
| European Union (REACH) | Chamber | mg/m³ | 0.062 limit from August 2026 |
| United States (TSCA Title VI) | Chamber | ppm | Hardwood plywood: 0.05 |
A perforator result, a desiccator result and a chamber result measure different things in different ways, so they cannot be converted into one another with a simple rule. An 'E0' or 'E1' label means little until you know which standard it refers to.
What to ask for
- The formaldehyde class under IS 303:2024, E1 or E2, marked on the sheet or covered by the licence.
- For any product sold as E0, the standard and test method behind the claim, and a recent test report.
- The class of the core itself. A laminate or veneer face does not change how the core is classified, so do not rely on the surface.
- MDF and particle board have their own Indian standards and requirements, so ask about each board type separately.
- Test reports from a laboratory recognised by BIS or accredited by NABL, rather than a figure printed only in a brochure.
Living with new furniture
The US Environmental Protection Agency's advice is practical: ventilate well, especially after bringing new board products into a home, and keep temperature and humidity moderate, since heat speeds up release. Edge-banding and finishing every exposed face also limits the area of bare board open to the room. With a new kitchen or wardrobe, keep the room ventilated for a while after installation rather than sealing it up straight away.
Common questions
- What is the difference between E0, E1 and E2 plywood?
- They are formaldehyde emission classes, with E0 the lowest, then E1, then E2. The limits depend on the standard. In India, IS 303:2024 uses E1 (below 8 mg per 100 g by the perforator method) and E2 (between 8 and 30 mg per 100 g). E0 belongs to other systems, such as the Australian desiccator scheme, so always ask which standard a label refers to.
- Does IS 303 have an E0 grade?
- No. IS 303:2024 classifies plywood into formaldehyde classes E1 and E2, measured by the perforator method of IS 13745, with an optional chamber test for steady-state emission. E0 is a class in other systems, such as the Australian and New Zealand desiccator scheme. A board sold as E0 in India should state which standard and test the claim is based on.
- Which formaldehyde class should I choose for a bedroom or wardrobe?
- Choose the lowest emission class you can obtain for rooms where people sleep or spend long hours, especially closed, air-conditioned rooms. Under IS 303:2024 that means E1 rather than E2. Ventilate well after installation, finish or edge-band exposed board, and keep the room at a moderate temperature, because heat speeds up formaldehyde release.
- How is formaldehyde emission from plywood measured?
- There are three common approaches. The perforator method extracts formaldehyde from an oven-dried sample and reports mg per 100 g; IS 303 and IS 710 use it. The desiccator method measures what a small sample releases into water, in mg per litre. Chamber tests, used in Europe and the US, measure release into air in mg/m³ or ppm, which most closely resembles a real room.