Tuesday, January 12, 2010

Safety Precautions and Hazards of Liquid Petroleum Products.

Although handling petroleum products presents many hazards, both bulk and packaged products can be handled safely if product characteristics are understood and proper precautionary measures are taken. Maintenance personnel should know the hazards in handling and storing aviation fuels come from both the fuel (toxic through skin contact or ingestion) and its vapors. Vapors from all petroleum products constitute fire and explosion hazards and are also toxic to the human body. Vapors from petroleum products have caused fires or explosions because the vapors are heavier than air and settle in low places such as tanks or pits. The vapors will remain in these low places indefinitely unless removed by ventilation. A detailed description of product characteristics is in MIL-HDBK-201B(1), Petroleum Operations, October 1, 1992, MIL-HDBK-1022A, and AFOSH Std 91-38, Hydrocarbon Fuels, General.

Toxic Liquids, Vapors, and Dust.

1. Liquids

 Most petroleum products are toxic because of their aromatic content or additives (especially tetraethyl lead). Avoid getting jet fuel or gasoline on the skin and clothing. Because JP-8 has fewer aromatics than JP-4, it does not evaporate quickly. This means skin contact is more likely to result from fuel on clothing. Jet fuel and gasoline remove protective oils from the skin, causing drying, chapping, and cracking that can lead to infection and possible blood poisoning. Severe chemical burns may result if jet fuel and gasoline remain in contact with the skin. Shower and remove contaminated clothing at once and avoid any source of ignition. Remove jet fuel or gasoline from the skin by washing with soap and water as soon as possible after contact. Remove fuel that comes in contact with the eye immediately with the eye bath or any other available means of flushing the eye with water, and secure medical attention as soon as possible. Accidentally swallowed petroleum products may cause central nervous system depression and pneumonia. Do not induce vomiting and do not allow the victim to smoke! Victims should be taken to a medical facility at once. Be sure to inform medical authorities of the type of fuel and approximate amount ingested. Liquid contact with the skin may also affect the liver, kidneys, or bone marrow, due to additives or contaminants such as benzene. Use disposable fuel-resistant coveralls to reduce fuel absorption. Replace coveralls contaminated with fuel.

2. Vapors.

Vapors accumulate inside enclosed areas (such as tanks and pump houses) and settle in low areas (such as pits and valleys). Promptly report all physical reactions resulting from jet fuel or gasoline vapor inhalation to a physician, even though rest and fresh air may cause recovery within a few hours. To eliminate personnel hazards of vapor concentrations, follow AFOSH Std 91-25, Confined Spaces.

3. Dust.

Eliminate most toxic dust by properly disposing of sludge and cleaning waste.

Personal Clothing.

The hazards of working with JP-8 have added a new concern in selecting personal clothing. Although static electric buildup must still be considered, absorbing fuel components through the skin is important as well. The conventional 50% polyester and 50% cottonblend coveralls used by LFM for years do not provide adequate protection from fuel absorption. JP-8 in contact with the fabric tends to wick from a small contact area to a much larger area, increasing the contaminated area in contact with the skin and causing skin irritation. Although the 50/50 blend is adequate for routine work, the coveralls should be changed if contaminated with fuel. When working in a fuel-intensive environment, such as tank cleaning, use a disposable Tyvek coverall having a static-dissipating coating. This may be worn alone or over the cotton-blend coveralls. In tests, no protective product totally prevented JP-8 from passing through. The exposure area was low because the wicking effect was not present. Because of this, replace Tyvek coveralls that become contaminated. Fuel tank cleaning crews using Tyvek coveralls as the only garment have not experienced the skin problems encountered using the 50/50 blend.

 NOTE: The static-dissipating coating on Tyvek coveralls is water-soluble. Loss of the coating should not be a problem during low lower explosive limit (LEL) conditions. Use properly coated coveralls during the initial opening of a tank when explosive vapor levels may be present outside of the tank (paragraph 8.4.2). When wearing Tyvek coveralls, take the same precautions as with the 50/50 blend, and ground yourself periodically to remove static charges.

Studies have identified the greatest static charges were created during the replacement or removal of outer garments such as field jackets and parkas. To end this hazard potential,  personnel must not put on or remove such garments while engaged in fuels handling or servicing operations.

Civilian or military clothing of all wool, silk, or nylon materials, or blends of silk or nylon, generate far greater electrostatic charges and constitute an unacceptable hazard potential; therefore, clothing made of these materials must not be worn as outer garments during fuels servicing or handling operations. Wool stockings, wool glove inserts, woolen navy stocking caps (where authorized), and underwear of nylon, silk, or polyester poses no significant hazard and are acceptable.

Foul weather gear is allowed in Table of Allowances (TA) 016, Table of Allowances for Special Purpose Clothing and Personal Equipment, for LFM personnel who are subject to outside work during inclement weather. Any type of clothing may be worn as outer garments when working with high-flashpoint fuels (JP-5, JP-8, JP-10, Jet A, Jet A-1, or diesel). However, when servicing aircraft with low-flashpoint fuels (JP-4, Jet B, AVGAS, MOGAS), clothing containing more than 65% of any combination or mixture of nylon, rayon, wool, or polyester must not be worn (T.O. 00-25-172, Ground Servicing of Aircraft and Static Grounding/Bonding, paragraph 4-16d).

Seismic Energy Dissipation Devices

Seismic Energy Dissipation Devices