Safety Hazards of Hydrogen

Hydrogen was first recognized as an element in 1766 by Henry Cavendish. It is the lightest, as well as the simplest, element. It is also the most common element in the universe. Hydrogen is a colorless, odorless gas that is highly flammable. Since it is such a light element, hydrogen is rarely found on the Earth in its free form because it simply escapes from the atmosphere. The major location of hydrogen on this planet is in water (H2O).

Fire

• Hydrogen is highly flammable.

  Fire is a primary safety hazard of hydrogen because of its highly flammable and combustible nature. A typical scenario that results in a hydrogen fire is when hydrogen is released and subsequently combines with an oxidizer, forming a combustible mixture. Once this mixture contacts an ignition source, a fire will result. Accidental burns are common because of the almost invisible flames the mixture produces. It is important for hydrogen to be properly stored away from heat, flames, and sparks.

Combustion

• Hydrogen is highly combustible.

  When hydrogen changes from a liquid to a gas, significant expansion takes place, which can create an overly pressurized situation, resulting in a rupture. Injuries may occur from flying fragments of a ruptured vessel. The hydrogen released during a rupture is once again a fire hazard as it meets potential ignition sources. Hydrogen is stable under normal heat and pressure conditions, but contact with metals, oxides, or halogens may also result in combustion, so it should be stored away from other materials.

Frostbite

• Hydrogen in its liquid form can cause severe damage to skin.

  Hydrogen in its liquid form is used as a cryogenic for storing items at extremely low temperatures. Unintentional release of liquid hydrogen can result in frostbite or severe blistering if it comes in contact with the skin. The affected area should be flushed thoroughly with warm--not hot--water. If warm water is not available, wrap the affected parts in blankets.

Inhalation

• Because of hydrogen's odorless, colorless, and tasteless properties, it is not easily detectable, which can result in accidental inhalation. Short-term exposure can cause nausea, vomiting, dizziness, suffocation, convulsions, and coma. Immediate medical attention is required if hydrogen is inhaled so that oxygen can be administered. Hydrogen should always be stored in a well-ventilated area. Hydrogen sensors that will detect leaks should be installed in storage areas.