The national standard for household floor density is 860, but we have measured it to reach 880 or above. The rule for household floor wear is ≥6000 rpm, but we have measured it to reach 9000 or more, but as a pro, the most concerned is the floor. Environmental protection, solemn commitment in this floor, the formaldehyde emission of the series is 0.3mg/L! It has fully met the national requirements for E1 (formaldehyde release ≤ 1.5mg / L), and even has reached the E0 (formaldehyde emission ≤ 0.5mg / L) level standard.