Mine Ventilation – A Critical Safety Concern

Mines (and the necessity of proper mine ventilation) remain a critically important part of the United States economy. In fact, according to the United States Center for Disease Control, “in 2013, there were a total of 13,604 mining operations that reported mine operator employment.” This figure does not even include the thousands of additional mining operations throughout the rest of the world. However, underground mines are dangerous work environments filled with noxious contaminants which may include dust, diesel fumes, dirt particulates, and fumes, and gases released from the rocks. These chemicals are spread through mine shafts by diesel engine exhausts, the blasting of explosives, and the ore body itself, which places harmful chemicals into the air. As a result of these dangerous fumes being produced, it is essential that a powerful, efficient, and durable mine ventilation system be in place to transfer out the hazardous fumes and replace them with a fresh supply of clean air. At Ducting.com, we offer a wide range of mining hoses designed to keep this airflow moving to protect the health of mine workers and maintain the efficient operation of equipment.

If there is one ducting application where reliable flexible hoses are critical, it is in the application of mine ventilation. Without proper gas exchange taking places, mines are unsafe and cannot be used for their intended purposes. A mine duct helps to dilute and freshen critical air in mine’s working spaces. A powerful and efficient primary ventilation system is essential to maintaining high-quality airflow in a mineshaft. To ensure that a strong airflow is accomplished, it is important to use durable and large diameter mining hoses. We offer several options of large diameter mine ducting that allow large amounts of air to flow from powerful ventilation fans. For heavy-duty air transportation, several of our mining hoses are available in custom diameter sizes up to 60 inch ID. These extreme sizes of flexible hose help to transport air oxygen into even the deepest parts of a mine, while simultaneously removing carbon dioxide and other harmful gasses to the surface.

It is not only important that underground mine ventilation transfer in a healthy air supply, but the freshening of the air must also be able to control the air temperatures within the space. Our mine ventilation duct products work well with a variety of heat systems because they feature a wide temperature range. Whether it coal, iron, or silver, temperature extremes are not uncommon to mines of all types.

The Air Ventilator Series of Flexible Ducting

The Air Ventilator Ducts are available in 4 colors (Orange, Yellow, White, and Black) and sizes from 4-inch diameter to 24-inch diameter from inventory. These are the ideal affordable mining ventilation hoses that offer excellent lifecycles in the abrasive exterior conditions. These are lightweight and easy to transport hoses that compress for easy moveability. This highly compressible hose has a 9 to one compression ratio, meaning the standard 25ft length compresses down to just under a three-foot length. The exterior of these flexible ducts have a wearstrip and that allow this hose to be dragged in rough mining conditions and be protected from external abrasion vie these wearstrips. Made from a polyester fabric that has been coated with a polyvinyl chloride cover makes this product an excellent hose for mining ventilation.

Highlights

• In Stock for Shipping within 24 hours
• Stocked sizes: 4, 6, 8, 10, 12, 14, 16, 18, and 24 Inch I.D.’s
• Perfect for small or large confined spaces
• All hose ends have a belted cuff
• Extremely easy to install
• Wearstrip offers external abrasion resistance
• Ideal duct for mining blower applications

A Brief History of Mining

Mines did not start out as a place extract a resource. Mines had been a cavern of safety from the wild elements in nature. Humanity used caves and fissures to hide, rest and protect its young. It is possibly here that humanity learned to excavate and use the resources their caves offered. The process of mining may date back to centuries before Christ when primitive societies mined flint. Flint is a stone which is very hard and durable, making for a tool or weapon since it breaks into shards with sharp edges. Discoveries made by the excavation of mines has offered animal figures carved into the shaft walls by these early inhabitants of mines. It is safe to say a good and lucky portion of humanity were miners, since they lived in caves and earth’s fissures. As humans began digging caves so that their homes became more expansive, they dug into spaces that offered resources other than space. Digging up resources from the earth ever since has been a necessary vocation for humankind. About 5000 BC, the natives of modern America’s found a treasure in their caves, and these were copper veins. Copper allowed for the development of more sophisticated hunting tools, fishing gear, and jewelry. During the colonial era iron ore was mined sent to England from near Jamestown. Then the gold rush that started on the East coast of the colonies went west and the California gold rush of 1848 set off a shift in the geography of the United States. The west was no longer a wild patch of never ending lands and the source this new wealth made mining even more of an economic resource. As the Industrial Revolution bloomed in the United States, the demand for coal increased. The need for this energy source helped steam engines and the new Northeastern factories gain a domestic and dependable energy source. America has not looked back since and even though mining does neither have the political nor the social sex appeal, it is and has been the backbone of America’s progression from a farming economy into the greatest economic engine in the history of humanity.

Today, there are over 13,500 active mines in the United States that most commonly produce, industrial metals (e.g., iron, copper, steel, uranium), precious metals (e.g., gold, silver, platinum) energy sources (i.e., coal) and minerals (e.g., crushed stone, cement, gravels, sand).

What Gases are Released When Mining?

The types of gasses released in mines should split into three groups. The first are those that cause asphyxiation, the second are toxic gasses and the third are flammable gasses. The list of toxic gases in mines is very long and elaborate but regardless of the types, all three groups pose safety dangers to miners and the industry.

1. What are the toxic gases in mines?
   Gases such as sulfur dioxide, hydrogen chloride, cyanides, and hydrogen sulfide are ones that are toxic and are released during mining. Sulfur dioxide is severely irritating to the eyes, mucous membranes, skin, and most importantly affects the respiratory system, particularly lung function. Hydrogen chloride
   Hydrogen chloride forms in a corrosive fashion when hydrochloric acid on contact with water found in body tissue. Inhalation of the fumes can cause coughing, choking, inflammation, circulatory system failure, and death. Skin contact can cause redness, pain, and severe chemical burns. Cyanides are used in a process called Cyanidation where a sodium cyanide solution is commonly used to leach gold from ore. Exposure to cyanide can cause coma and death.
2. What gases released during mining cause asphyxiation?
   Carbon dioxide (CO2), nitrogen (N2), and methane (CH4) are gases that are generated as a result of mineral oxidation in a mine. One such culprit is decaying wood. It is estimated that decaying forests release a monstrous 10.9 billion tons of carbon each year and this is in the form of carbon dioxide. Another type of chemical weathering works in mines is on rocks that contain iron. These rocks turn to rust in a process called oxidation. Oxidation is a chemical reaction that takes place when oxygen reacts with an element like iron. Oxygen is very strongly chemically reactive. This reduces the oxygen level in a confined space like a mine and can cause suffocation. The concentration of oxygen in air is around 21% percent and when it starts to decrease to below 18% percent breathing becomes considerably difficult. Faintness, vertigo, and ocular loss begin at 15% percent oxygen levels and loss of awareness and death are seen below 9% percent oxygen levels.
3. What is the most dangerous gas in a mine?
   Carbon monoxide is among the most toxic gases in a mine. The drill-and-blast method is widely used for the excavation of hard rock tunnels. Carbon monoxide and nitrogen oxides are the byproduct of blasting using explosives. Breathing high levels of the gas causes severe illness or death in just minutes due to CO poisoning. Carbon monoxide, or CO, is a toxic gas that you cannot see or smell. Hypoxia (severe oxygen deficiency) due to carbon monoxide poisoning can result in negative neurological effects (e.g., brain damage) or cardiological (e.g., vascular damage) effects.

Insulated Flexible Ducts for Mine Ventilation

Insulated hoses are used in mines when air conditioned and fresh ventilation is being moved into spaces that are being used by miners. Insulated mine ducting is more expensive than its non-insulated versions, therefore should not be used when air is being ventilated out of a shaft, rather only when heated or cooled air is moving into the mine. Highly compressible and flexible ducts that have an R value that can maintain the temperature being moved through a hose, offer portable air conditioning units a very valuable means by which they can convey and maintain heated or cooled air in temporary spaces.

In the mining industry a large portion of downtime and work interruptions is due to equipment damage due to wear. Equipment will wear faster than it will corrode or be damaged by weathering. In this vein, mining hoses need to be inexpensive so that the costs borne by their replacement do not inflate any budgetary limits. In addition, they need to be protective enough so as to be able to withstand the abrasive wear the mining ducts are exposed to. Wear resistant mining ventilation hoses will help to reduce this marginal cost.

Here are three portable and insulated flexible ducts that are recommend for portable mining ventilation.

Wind Handler Insulated TU
Temperature Range: – 40°F to + 250°F
Sizes I.D. (inches): 4” to 24” and Custom ID sizes up to 48 Inch I.D.
Wearstrip offers additional external abrasion & drag resistance
High compressibility allows for convenient storage
Manufactured with flame retardant materials
Made with sewn cuffs on each end
Insulation R-Value of 4

Tornado-Flex Insulated AD
Temperature Range: – 20°F to + 180°F
Sizes I.D. (inches): 4” to 24” and Custom ID sizes up to 48 Inch I.D.
Ideal use for permanent and mobile air conditioning units
Made from highly durable PVC
Highly Compressible
Wearstrip offers additional external abrasion & drag resistance
Manufactured with flame retardant materials
Made with sewn cuff on each end
Insulation has R-Value of 4

Air Ventilator Insulated
Temperature Range: – 20°F to + 180°F
Sizes I.D. (inches): 8, 12, 14 and 16 Inch I.D.
Compressible and easy to transport
Insulation maintains temperature of air inside hose
Very cost-effective insulated duct

Ventilation Safety Systems in Mines

As you would expect, the most mined commodity in the USA is coal. And workplace safety is of the utmost concern of the industry, despite the bad press! A culture of safety in an industry describes the behaviors that culminate in the collective industry and nonstop commitment by administrative leadership and workers to emphasize safety over other goals. The main goal of safety and health programs is to prevent workplace injuries, illnesses, and deaths, as well as the suffering and financial hardship these events can cause for workers, their families, and employers. The prevent workplace injuries and illnesses is of the utmost concern of the mining industry and having clean, fresh air and ventilated mine shafts is one major focus. Providing sufficient air quantity in a mine is the main driver of guaranteeing that incendiary, volatile, lethal, and harmful gases, dusts, fumes are diluted. As required by “Section 303 of the Federal Mine Safety and Health Act of 1977. It is essential to miners’ safety and health that each working face is ventilated by sufficient air quantity. “

In mines, ventilation systems are established to delivering breathable fresh air so that either the fumes or impurities are diluted or completely removed. This ventilation also controls the temperature and humidity of the air. Mine ventilation hoses also protect the miners by clearing hazardous gases from the coal mine, as noted in our earlier discussion of the types of lethal gases in mines. Gases like methane are diluted to non-explosive concentrations by the use of mine ventilation hoses as the duct that bring in fresh air.