Abstract:Abstract:Based on JJF 1059.1-2012 Evaluation and Expression of Uncertainty in Measurement,the uncertainty for determination of formaldehyde emission of blockboard was analyzed. Uncertainty components of measurement were made sure by calculation.The combined uncertainty and expanded uncertainty were calculated. The results showed that formaldehyde emission was(1.3±0.2)mg·L-1, which expanded uncertainty coverage factor k=2, fiducially probability P=95%.