3.3. Formaldehyde emission
The addition of walnut/almond shells into particleboard signif-icantly decreased formaldehyde emission value (Fig. 6). Depending
on addition of walnut/almond shells in the panels, the formalde-hyde emission values ranged from 5.7% to 42.8% lower than the
panels made with 100% wood particles. The minimum value of
formaldehyde gas emission was measured for panels made with
100% walnut shell. In exact word, panel type F had the lowest
formaldehyde emission value with 4.9 mg/100 g (42.8% less than
panel type A) followed by panel type E (36.3%), panel type D
(16.3%), panel type C (13.2%), panel type B (5.7%) and finally panel