Do Electrical Hazard Work Boots Have to be Composite Toe?

There seems to be some controversy on whether a safety shoe with a steel toe can meet the ASTM Electrical Hazard Standard.  The answer is, yes it can!  Safety Shoes have had Electrical Hazard Standards for many years, even predating the development of Composite Material Safety Toes, so prior to Composite Toe Safety Shoes, all Electrical Hazard Safety Shoes had Steel Toes.

The Electrical Hazard test checks the ability of a new safety shoe to prevent an electrical charge leaking through the outsole into ground, and the safety toe type has nothing to do with the success or failure of this test.  The Electrical Hazard safety shoes have to be built to hold the charge of 18,000 volts, at 60 Hz, for 1 minute, with no current flow or leakage to exceed 1.0 milli-amperes under dry conditions.  The American Standard (ASTM 2413-11 Section 5.5 and ASTM2412-11) and the Canadian Standard (CSA Z195-09) for Electrical Hazard and/or Electric Shock (as the Canadians call it) were made the same in 2011 when the American Standard was changed effectively to be the same as the Canadian Standard.  Thus this change eliminated the confusion about which standard was the strongest standard.  They are both the same.

The standard does say that no metal may be used in the construction of the sole, but I believe some people think this includes the safety toe.  It does not!  This does mean that the shank of the safety shoe has to be made of a non-metallic material, and neither nails nor screws can be used in the heel or sole construction, unless they are made with non-metallic materials. 

Prior to the onset of Composite Toe safety shoes, all Electrical Hazard safety shoes were steel toe, and today plenty of steel toe, Electrical Hazard safety shoes are available.

So what if the steel toe touches an electrical source.  Well, the sole is still going to protect the wearer because the sole and the sole’s construction are what insulate the shoe and the wearer from being grounded.  So what if the wearer is kneeling down and the steel toe is touch the ground and the person contacts a live electrical source?  The grounding will take place, but the electric current will be grounded through the person’s knee, which is touching ground.  So what if the leather covering the steel toe is exposed; does that have an effect?  No, because the sole and the sole’s construction is still insulating the wearer and the shoes and keeps them from being grounded.  (NOTE:  Any safety toe shoe with the leather worn off of the safety toe and the safety toe showing, should be replaced immediately.)

A couple more notes:  Electrical Hazard safety shoes are only meant to be a secondary source of protection from high voltage environments, never as the primary source of protection.  So, if the Person wearing Electrical Hazard Safety Shoes knows he is going to be in a Hazardous Electrical Environment, all primary means of safety and protection from the Electrical Source should be employed.  Additionally, Electrical Hazard safety shoes are tested in the perfect environment of a laboratory and in NEW CONDITION.  Over time, wearing these shoes makes them less effective protection because the thickness of the sole is reduced and that lessens the soles insulating capabilities.  That happens regardless whether the safety shoe is a steel toe or a composite toe though.  The safety toe material has no effect on the effectiveness of Electrical Hazard Safety Shoes.

What’s the Difference in Protection You Get From Electrical Hazard (EH), Conductive (CD), and Static Dissipating (SD) Footwear and How Do They Work?

The difference in protection is that Electrical Hazard shoes reduce the possibility of electric shock or electrocution, while Static Dissipating and Conductive shoes reduce the possibility of static discharge and static shock.

Electrical Hazard Shoes Provide you with a Secondary Source of Protection from Electric Shock or Electrocution
Electrocution (fatal and non-fatal) is the massive flow of electrical current through a person causing physical damage to the muscular and nervous system. Protection from electrocution is accomplished by insulating the body from physically contacting an electrical source with non-conductive material.

Example: Copper wire, used to wire houses, can be handled manually even though it has electricity flowing through it because the copper wire is wrapped with a non-conductive material (sheath) that protects you from the electrical source. If you touch the copper wire directly while an electric current is passing through it, you will receive an “electrical shock” or be electrocuted.

Electrical Hazard (EH) shoes provide a secondary source of protection for you from electric shock or electrocution the same way as the sheath of the electrical wire. Electrical Hazard shoes have a special sole and construction that insulates you from the electrical source. The special sole is composed of non-conductive and electrically insulating materials, that won’t conduct electricity. These shoes are said to have a high resistance to “electrical current” or the “flow of electricity”.

Technically, these special shoes are rated in the highest range of Resistance for safety shoes at 1 GigaOhm (1 Billion Ohms, 1,000,000,000) of Resistance or higher, which is required by ASTM Standards for all Electrical Hazard safety shoes; and they are designed to resist an electric charge of 18,000 Volts at 60 Hertz for 1 minute with less than 1 milliamps of leakage in dry conditions. Electrical Hazard shoes, or non-Conductive shoes as they are sometimes called, are designed to be use only as a secondary source of electrical hazard protection, but they provide very good protection for Electricians and others working with dangerous, open, electrical circuits.

Conversely, Conductive shoes are designed to make it easy for electricity (specifically, static electricity) to flow from the wearer through the shoes to ground, in order to suppress the occurance of static electricity, static discharges, and static sparks . People working in highly flamable and explosive environments have to wear this kind of footwear because the smallest spark can cause a catastrophic explosion or fire.

Technically, Conductive shoes have special materials in the sole and specific construction techniques that create a very low electrical Resistance (0 Ohms to 500,000 Ohms) in the shoe, so electrostatic charges on the wearer are eliminated when they flow very easily and quickly through the shoes to ground. People working in dangerous, highly flamable and explosive environments have to wear this kind of footwear because the smallest spark can cause a catastrophic explosion or fire.

Static Dissipating (SD) Shoes are very similar to Conductive (CD) Shoes because they do the same thing–prevent static discharge sparks by channelling static electricity from the wearer through the shoes to ground. Technically, the difference in the Static Dissipating (SD) and Conductive (CD) shoes is SD shoes have slightly higher resistance (1,000,000 to 100,000,000 Ohms versus 0 to 500,000 Ohms for CD footwear), which causes Static Dissipating SD shoes to dissipate static electricity a little slower than Conductive shoes do. This is OK because they are used in less “hazardous” environments, like environments where printed circuit boards are vulnerable to static sparks and environments where static electricity discharges are a real nuisance!

In summary, Electrical Hazard (EH) shoes protect people from electrocution because they are built to be “non-conductive” and prevent the flow of electricity through them, and conversely Conductive (CD) shoes protect people from explosions and highly flamable environments because they are designed to “conduct” static electricity and eliminate electrostatic discharges and sparks. Static Dissipating (SD) shoes work the same way as Conductive shoes, but they are used in less dangerous environments ,like around printed circuit boards and where static sparks are a serious nuisance for workers.

EXPLANATION OF CHART:
The higher the Electrical Resistance (Ohms, MegaOhms, GigaOhms) rating in the shoe, the more resistance there is to the flow of electricity from the wearer through the safety shoes to ground. And conversely, the lower the Electrical Resistance (Ohms, MegaOhms, GigaOhms) rating in the shoe, the less resistance there is to the flow of (static) electricity from the wearer through the safety shoes to ground.

The lowest resistance range is for Conductive (CD) shoes, which drastically reduces the build up of static electricity. Static electricity will flow easily from the wearer through the safety shoes to ground, and that keeps the wearer from creating a spark when touching anything . This is critical for explosive and very flamable environments, where a spark can be catastrophic.

Going up the scale, the next range of Electrical Resistance is for Static Dissipating (SD) shoes, which allows for enough flow of static electricity to eliminate nuissance sparks and sparks that could damage printed computer circuitboards

Finally, the highest range of Electrical Resistance is for Electrical Hazard (EH) shoes, which are non-conductive and impede the flow of electricity, thereby previenting the wearers, like electricians, from electrocution and electrical shocks from open circuits of electricity .

If you have any questions, post a comment below!

Electrical Hazard, Static Dissipative and Conductive Safety Shoe Information

What’s the difference between Electrical Hazard, Static Dissipative, and Conductive Safety Shoes?

The 3 distinct types of conductivity found in Safety Shoes are Electrical Hazard (EH), Static Dissipative (SD), and Conductive (CD).  These are tested according to the ASTM (American Society of Testing and Materials) standards F2412-05 and F2413-05.

EH Electrical Hazard Safety Shoes

The differences between these classifications of Safety Shoes are that Electrical Hazard shoes are designed to impede (reduce significantly) the flow of electricity through the shoe and to ground, thereby reducing the possibility of electrocution. Electrical Hazard Safety Shoes will have an “EH” clearly visible on the ASTM label sewn inside the safety shoes.  (ASTM F2413-05 Sec. 7.1.5.2)   Only safety shoes can have the Electrical Hazard designation.  (ASTM F2413-05 Sec. 5.5.1),

IMPORTANT:    Electrical Hazard shoes are not designed to be the primary source of protection in an Electrical Hazard environment.  They are designed to be only a secondary source of protection in an Electrical Hazard environment, and that is clearly stated in the ASTM standards for Electrical Hazard Safety Shoes.  (ASTM F2413-05 Sec. 5.5.4 & Sec 5.5.2),

SD Static Dissipating Safety Shoes and non-Safety Shoes

Static Dissipating Safety Shoes and Soft-Toe shoes are designed to dissipate (reduce) the amount of static electricity build-up on your body.  Unlike Electrical Hazard Safety Shoes, Static Dissipating Shoes can be either safety toe or non-safety (or soft-toe).  Static Dissipating shoes actually conduct static electricity through the linings and insole, cement, and outsole and into ground.  Static Dissipating Safety Shoes and non-Safety Shoes have a “SD” clearly visible on the ASTM label sewn inside the safety shoes.  (ASTM F2413-05 Sec. 7.1.5.3),

To accomplish Static Dissipating environments consistently, several things must be controlled.  First, you cannot add any kind of insole to the shoe, except a specially designed Static Dissipating insole.  If a non-Static Dissipating insole is added to the shoe, Static Electricity will not flow through the insole.  When the insole becomes non-conductive; the shoe will not Dissipate Static Electricity.  Also, the floor and sole of the shoe must remain clean and free of dust and other foreign matter to maintain good contact between the sole and the floor.  This allows the Static Electricity to Dissipate, or flow through the sole and into ground.  (This assumes that floor is “grounded” and Static Electricity will flow through to the floor material.) 

Static Dissipating Shoes and Safety Shoes are worn in mainly two types of environments:  Computer component handling facilities and nuisance Static Electricity environments, like plants where the process and machinery create a large Static Electricity field in the manufacturing process.  Typically, this field creates a build-up of static electricity on employees working in the environment, and then discharges when the employee touches metal that goes to ground or has a neutral or less charge than the body has.  This Static Discharge “shocks” the person, creating momentary discomfort and annoyance. Static Dissipating shoes can help this situation, but the floor, mats, and machinery, also need to be grounded to reduce the Static Electricity field in the environment.

Conductive Safety Shoes

Conductive Safety Shoes are designed to “conduct” Static Electricity through the shoes and into ground.  Conductive Safety Shoes are similar to Static Dissipating Safety Shoes because both are designed to dissipate Static Electricity.  Conductive Safety Shoes (CD) Dissipate Static Electricity much faster and more completely than Static Dissipating Safety Shoes (SD). The reason is that Conductive Safety Shoes are worn in environments that are highly flammable and explosive, which means that reducing the possibility of a Static Spark or Discharge is critical to the safety of not only the employee, but the other employees in the immediate area and even citizens in the vicinity of the explosive area.  According to the ASTM Standard, Conductive (CD rated) Shoes must be Safety Shoes (ASTM F2413-05 Sec. 5.4.1), and the Conductive Safety Shoes have a “CD” clearly visible on the ASTM label sewn inside the safety shoes.  (ASTM F2413-05 Sec. 7.1.5.1),

Important:    Because Conductive Safety Shoes (CD) conduct electricity, employees wearing these shoes must avoid wearing Conductive Safety Shoes in Electrical Hazard (EH) environments.  Obviously, this could be a very dangerous situation.  (ASTM F2413-05 Sec. 5.4.2.3),