Metallurgy and Iron metallurgy
The heated chemical reaction between pyrite and coal in order to produce steel engenders many risks gas wise. In the blast furnaces coke is used as fuel and releases a highly toxic gas: cokery gas. This gas contains monoxide of carbon, sulphured hydrogen, methane, SOX, and NOX.
Lack of oxygen (O2): deficiency of oxygen is possible in all the closed spaces, in presence of other gases, or if the aeration conditions are reduced because of environmental circumstances.
Methane (CH4): also methane might need to be supervised. In some cases methane leaks in non-explosion-proof areas with the consequent risk of explosion.
Carbon monoxide (CO): this gas is often used in boilers to generate energy, as fuel in the blast furnaces, or reintroduced in the burning process. Leaks in the pipes or in the furnaces are quite common: the gas does not always spread in the atmosphere because usually the base of the furnace is a close cabin and the accumulation is very probable.
O2: both excess and lack of oxygen may cause important diseases, sometimes death.
CH4: methane is a simple hydrocarbon and is in nature in form of gas. Methane is the main component of natural gas and is an excellent fuel, able to form easily in atmosphere resulting in a high risk of explosion.
CO: carbon dioxide is a compressed colourless, odourless, tasteless and poisonous gas. Even short exposures to carbon dioxide may reduce oxygen concentration in brain so the victim falls unconscious and dies.