What Are the Dangers of Cleaning Blast Furnaces?

Explosion

• There shouldn't be a risk of explosion once a furnace is fully shutdown, but the cooling of the molten metal during normal operation and during a shutdown process in preparation for cleaning carries risks. As water is added to the iron to cool it, there is a risk that steam from the iron gets trapped under a crust of hardened ore that forms over the top. The pressure then continues to build until the crust cracks. At that point, the steam erupts explosively and molten iron is blown outward as a result.

Carbon Monoxide Inhalation

• Carbon monoxide gas is a common side effect of combustion, especially if fuels aren't burning at peak efficiency. Carbon monoxide can build up inside the blast furnace and should be ventilated out before any workers enter the vicinity. Carbon monoxide doesn't have any odor and exposure leads to dizziness, fainting and potential brain damage or death within minutes of high exposure. Carbon monoxide detectors are a vital safety tool for blast furnace facilities and carbon monoxide levels should be tested before a cleaning process begins.

Lead Exposure

• Lead is a byproduct of the blast furnace process and it is highly toxic. Lead particles can be inhaled by cleaning workers and the accumulation over time leads to potential trembling and paralysis. Workers may also develop a blue line across their gums, which is an indicator of lead poisoning. If the flue becomes blocked during operation and remains so during a cleaning process, lead dust doesn't escape the system effectively and the dust falls back into the main cavity, increasing the risk of lead exposure. It builds up inside the flue as well. Workers need to wear appropriate respirators and safety gear to protect against exposure.

Benzene

• Benzene is a carcinogen that that leads to leukemia and other cancers with any prolonged exposure. It is a common side effect of coke combustion. Coke is a carbon that helps fuel the blast furnace during the iron making process. It is a vital component but benzene is produced as a result in gaseous form. While it has many industrial applications, the Occupational Safety and Health Administration regulates how much exposure is permitted for blast furnace employees, cleaning crews and other workers.