To Use This nalyzer with safety and affectibeness, please read this manual befor usage. This manual applies to the product model QRO -401 (4/5 gas Analyzer)1. The manualshould be refemed with regard to the product design and safety assurance of the configuration. 2. For the purpose of safety confirmity, this manual should be provided to the end user ar the samae time with the supply of the product.