History

Early Foot Coverings

Shoes As Symbols

Modeling & Creation

Care Your Feet

Outline Of Footwear

Style and Fashion

Footwear Construction

Extra Protection

Glossary

Extra Protection

Electrical Hazard Designed to provide extra protection where accidental contact with electrically energized objects is possible (600 volts or less). To be effective, the leather must be dry. Electrical hazard footwear provides secondary protection on surfaces that are already insulated, and it is not intended for use where conductive footwear is required, such as explosive or hazardous locations. Each shoe must withstand the application of 14,000 volts for one minute and show no leakage current in excess of 5.0 ma. Footwear meeting standards for electrical hazard may bear a label . This reflects approved footwear that complies with the 1999 Z41 standard.

Electrical Hazard Test Methods Testing: The shoe to be tested is filled to a depth of 1" with steel BB shot. It is then placed on the metal mesh screen that forms the floor of the test chamber. The end of the metal chain that hangs from the top of the test chamber is buried in the steel shot. The metal chain and steel shot act as the inside electrode and the metal mesh screen floor acts as the outside electrode. When the test voltage is applied, the circuit from the chain/BB shot to the wire mesh floor cannot be completed unless there is a leak in the shoe. The test voltage is either 14,000 or 20,000 volts depending on the type of shoe being tested. The voltage is applied for one minute. Maximum leakage of 5.0 ma is allowed.

There are several variations of this test. Safety & Industrial uses the following: The shoe to be tested is filled with water to within 2" of the top of the shoe. It is then placed in the test chamber. The test chamber contains water that is at the same level as the water inside of the test shoe. An electrode is inserted into the water inside of the shoe. 14,000 or 20,000 volts are applied for a period of one minute. The circuit from the water inside of the shoe to the water outside of the shoe cannot be completed unless there is a leak in the shoe. Maximum leakage of 5.0 mA is allowed. The label signifies that this footwear is designed to pass the testing requirements of the "Standard Specification for Dielectric Overshoe Footwear". The test method, in summary:

Overshoe is filled with water, and immersed in a tank of water. The water inside and outside the overshoe are electrically charged, both bodies of water becoming electrodes. The height of the water inside and outside the boot is determined by the voltage used for the test - the higher the voltage, the more gap is allowed between the two water levels. For 20 KV, this "flashover clearance" is 5 inches (127 mm), or 2.5 inches from the top of the boot, for both the inside and outside water levels. Voltage is smoothly applied to 75% of the required test voltage, then applied at a rate of increase of 1 KV/sec. until the required test voltage is reached. The required test voltage is held for not less than 1 minute, and not more than 3 minutes (unless the boot fails the test).

Material used to make the dense foam midsole. Good shock absorbing properties.
Floating Metatarsal Called a "Floating Guard" because the guard is not anchored to the boot bottom and does not wrap around the sides of the foot. The guard is attached to the steel toe cap.
Full Metatarsal Guard is anchored to the boot bottom and wraps around the sides of the foot.
Impact and compression requires all approved footwear to offer impact and compression resistance. There are three different classifications for impact and compression ratings: 30, 50 and 75. The unit of measurement for impact ratings is foot pounds. These ratings indicate the shoe can withstand impacts up to number of foot pounds. For compression classification, these numbers stand for: 30=1000 lbs; 50=1750 lbs; 75=2500 lbs.
Insole The padded surface upon which the foot rests within the shoe.

Last the mold or form around which the shoe is shaped during construction. The last determines the shape and eventual fit of the shoe. Lasts can be straight, semi-curved or curved; shoes built on different types of lasts provide different types of support. Lateral Support Support provided along the outer side of the shoe
Leather Groups Boots are generally referred to by group names which correspond to how high the top line comes on the foot. The following are the most common groupings.  Top line finishes just below the ankle. The closure system is usually lace-up.

Chukka: Top line finishes just above the ankle. The closure system is usually lace-up. 6" and 8": Top line finishes either 6" or 8" up measured from the inside of the boot to the top line. Closure system is usually lace-up.

Wellington: Top line finishes 8" or 10" high. It has no closure system, and is pulled on over the foot.

Hiker: Top line usually finishes just above the ankle, as the Chukka. The closure system is lace-up. The styling is usually more outdoor oriented than a Chukka.

Leather Technical Facts Water-resistant: describes leather that has been tanned to resist moisture penetration, allowing water and other liquids to run off in order to keep the foot dry.
Waterproof: describes leather than has been tanned and treated so that water cannot penetrate and the foot is kept dry under all conditions.

Full Grain: refers to the outermost layer of layer whose grain has not been corrected or reduced. This is the highest quality leather available.

Barnyard Acid-Resistant: Specially treated for the unique elements associated with farms including manure, urine, fertilizers and herbicides.

Polishable: refers to leather than can be polished, is easily cleaned and has a tight surface to reduce absorption. Stain-resistant: Leather that has been specially tanned and treated to reduce absorption and resist stains.

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