P2 wood refers to composite wood products that meet the Phase 2 formaldehyde emission standards set by the California Air Resources Board (CARB). These are the strictest widely adopted limits on how much formaldehyde a wood panel can release into the air. If you’ve seen “CARB Phase 2 compliant” or “P2” on a product label, it means the material has been tested and certified to emit formaldehyde below specific thresholds that vary by product type.
Why Formaldehyde Standards Exist for Wood
Most composite wood products, including plywood, particleboard, and medium-density fiberboard (MDF), are made by bonding wood fibers or veneers together with adhesives. Many of those adhesives contain formaldehyde-based resins. Over time, the finished product releases small amounts of formaldehyde gas into the surrounding air, a process called off-gassing.
Formaldehyde is a colorless gas with a sharp smell. At concentrations above 0.1 parts per million in indoor air, it can cause watery eyes, burning in the eyes and throat, nausea, coughing, and difficulty breathing. People with asthma are especially vulnerable, and prolonged exposure at elevated levels is linked to cancer. Because composite wood is everywhere (cabinets, flooring, shelving, furniture), even small reductions in emissions per panel add up to meaningfully cleaner indoor air.
The Specific P2 Emission Limits
CARB rolled out its composite wood regulation in two stages. Phase 1 standards took effect in 2009. The tighter Phase 2 standards phased in between 2010 and 2012 depending on the product type. Here are the P2 limits, measured in parts per million (ppm):
- Hardwood plywood (veneer core or composite core): 0.05 ppm
- Particleboard: 0.09 ppm
- MDF: 0.11 ppm
- Thin MDF (8 mm or less): 0.13 ppm
These numbers represent the concentration of formaldehyde in the air inside a large test chamber after the panel has been placed inside for 16 to 20 hours under controlled temperature and humidity. The test method, known as ASTM E1333, uses a chamber of at least 22 cubic meters (about 800 cubic feet) to simulate real indoor conditions. The formaldehyde collected from the air is then measured chemically to determine whether the product passes.
P2 Is Now a Federal Standard
What started as a California regulation became the national baseline in 2017. The EPA adopted the same emission limits under TSCA Title VI, making them legally binding for all composite wood products manufactured, imported, or sold anywhere in the United States. The emission thresholds are identical to CARB’s Phase 2 numbers. A product labeled as TSCA Title VI compliant is accepted as CARB Phase 2 compliant, and vice versa.
There are minor administrative differences between the two programs. The federal rule requires three years of recordkeeping instead of CARB’s two, and imports must clear certification through U.S. Customs’ electronic system. But for consumers, the practical takeaway is simple: P2 compliance is the legal minimum for composite wood sold in the U.S. today.
How to Identify P2 Products
Manufacturers label compliant products in several ways. Common markings include “California 93120 Compliant for Formaldehyde,” “California Phase 2 Compliant,” “CARB P2,” or “TSCA Title VI Compliant.” You’ll typically find these labels stamped directly on the panel edge, printed on packaging, or listed on the product spec sheet. Retailers selling cabinets, flooring, or furniture made from composite wood should be able to confirm compliance if the label isn’t immediately visible.
Standards That Go Beyond P2
P2 is the regulatory floor, not the ceiling. Two additional designations exist for products with even lower emissions:
- ULEF (Ultra-Low Emitting Formaldehyde): Panels that emit formaldehyde well below P2 thresholds. Manufacturers must apply for and receive approval from CARB to use this designation.
- NAF (No-Added Formaldehyde): Panels made entirely with adhesives that contain no added formaldehyde. This doesn’t mean zero formaldehyde (wood itself naturally contains trace amounts), but no formaldehyde-based resin is used in production. NAF products also require CARB approval.
Both NAF and ULEF designations apply only to the raw panels themselves, not to finished goods like doors or furniture. If you’re especially sensitive to formaldehyde or want the lowest possible emissions for a nursery or bedroom, look for these labels on the panel materials specifically. Products made with NAF or ULEF panels still need to meet P2 as a baseline, but they typically come in far below it.
What P2 Means When You’re Shopping
If you’re buying cabinets, laminate flooring, shelving, or any furniture made from plywood, particleboard, or MDF in the United States, the product is already required to be P2 compliant. That’s the law. Where this label becomes more practically useful is when you’re purchasing imported goods directly (online marketplaces, for example) or buying raw sheet goods for a DIY project. In those cases, confirming P2 or TSCA Title VI compliance on the label or product listing helps you verify the material meets U.S. emission standards.
New composite wood products off-gas the most in their first weeks and months. Ventilating a room well after installing new cabinets or flooring speeds up this process. P2-compliant products still release some formaldehyde, just at levels low enough that, under normal conditions, indoor air quality stays within ranges considered acceptable by regulatory agencies.