Renab Kalon - NPR 1813The Renab Kalon is our favourite when it comes to office chairs that meet the NPR 1813 standard. Occupational health and safety standards are important for the health and well being of your employees. The standardisation is therefore based on the larger height of Dutch people. When buying the Renab Kalon, you're assured of an ergonomic seat. This reduces the risk of physical complaints when you sit at your workplace for hours.