Research purposes: Under the condition of natural ventilation,this paper analyzes and calculates the harmful gas concentration in each subsection of tunnel.

Aimed at tunneling ventilation in the underground engineering,the variation formulae of harmful gas concentration are deduced based on the analysis of gas motion and ventilation process under ideal condition.

Do well indoor environmental test and to avoid harmful gas pollution;

The research of harmful gas formation characteristic of coal-burning boiler operated by handwork;

Prediction and prevention of harmful gas in deep-lying long tunnel;

his experiment was conducted to evaluate the effect of EM on eliminating toxic gases (ammonia and hydrogen sulfide),odor,bacteria from stable and odor of chicken waste.

On noxious gas treatment in Xiasha east station of Hangzhou metro

Coal is one of China's primary energies,but coal mining has bought a series of problems such as environmental pollution,security, one of which is noxious gases,including CO,CO_2,CH_4,H_2S,NO_2,SO_2 and so on,they are commonly found in poorly ventilated old roadway,goaf and in the vicinity of the fire area and in the airflow of artillery smoke,methane and coal dust during the explosion.

This paper analyzes and evaluates the cabin noxious gas when the tank artillery fires.

Study on harmful gases detecting and warning technique;

The Efficacy that Infusion with Air Purifying Set Absorb Harmful Gases are Inquired;

Combined with experiences in actual construction management,the smoke and dust removal method of mobile wind blocking screen and the relevant equipment are developed,which can thoroughly improve the environmental quality of work sites and remove dust and harmful gases.