Written by David Weszely, Safety Training Manager at Lewellyn Technology
1. Will a 100 Cal/cm2 arc flash suit protect me better?
It’s not a good choice to buy a 100 Cal arc flash suit instead of a 40 Cal suit all because you think it’s going to provide more protection. Because of the energy produced in arc flash explosion above 40 Cal, electrical workers should always try and de-energize equipment or use remote devises. Purchasing or using a 100 Cal suit or higher can provide you with more protection, but the fact is the human body can only handle so much pressure from an arc flash explosion. Experts agree that any explosion over 40 Cal is too much for the body to handle and that de-energizing equipment is a much safer route. Purchasing a 100 Cal suit will provide a false sense of security; and in the event of an arc flash, the suit may survive, but you will not.
2. Are protective face shields the same as arc flash face shields?
Wearing a protective face shield that is not arc rated will not provide arc flash protection. Although they may look similar, a simple protective face shield will melt in the event of an arc flash event. Arc flash face shields are designed to protect the face from very high thermal heat produced during an arc flash event. Always make sure to check your face shield for the arc flash rating, which should be located on the shield itself. Note the NFPA 70 E requires the combination of safety glasses and an arc flash shield to provide proper arc flash protection.
3. Do I need to buy expensive arc flash clothing?
It is very important to determine first how much the clothing will be used. Will your arc flash clothing be used daily or used occasionally a few times a year? It is also important to understand that arc flash clothing and arc flash suits need to be tested and approved before they are sold, but the quality of the fabric material is up to the manufacturer. Example: If you only use an arc flash suit on occasion, then buying a lower priced suit may be a better decision, because it will not wear out, nor need to be washed. It is important to understand that both priced suits will protect you from an arc flash. It is up to you to determine the amount of wear frequency the suit will have.
4. Do I have to wear thick leather gloves for arc flash protection?
It is important to understand that gloves used for shock and arc flash protection have come a long way and have enabled the user much dexterity to do their task without any handling problems. Voltage-rated rubber insulated gloves must be worn with leather covers to provide the appropriate arc flash and shock protection. Selection of gloves depends on the voltage that you will be working with or troubleshooting on. Most electrical tasks involve work under 500 volts. If the voltage is below 500V, then 00-insulated gloves are only required. These insulated gloves are thin rubber; and when worn with goat skin leather covers, they allow electrical workers increased dexterity and ability to complete troubleshooting voltage measuring tasks without a problem. Note: As the voltage increases, so will the thickness of the rubber insulated gloves.
5. Is it important to check my voltage-rated rubber insulated gloves for cuts and holes before using?
In an event of an electric shock, electricity will follow through the path of least resistance, passing through any hole or cut in the rubber insulated glove. If you’re going to wear voltage-rated rubber insulated gloves for shock protection, you need to check before each use for any holes or cuts in your rubber insulated gloves.
6. Should I buy EH Boots (Electrical Hazard) for better shock protection?
It is important to understand that EH rated boots are different then dielectric boots that must be tested on a regular basis. EH rated boots have protective insulating qualities that over time will break down and may not provide the same protection as when you first purchased them. As the souls of the boots wear out, the insulating qualities reduce. It is for this reason that EH boots are considered a good secondary, not primary, level of protection. Note: EH boots, if maintained and replaced when worn, will provide added electrical insulating qualities and protection.
7. When it comes to purchasing arc flash PPE, is it important to involve your workers?
Because comfort and feel is very important to people, it’s crucial that you involve the workers wearing the clothing and PPE, to try it on before they are made to wear it regularly. There are many choices in the market today. And if you want your employees to wear their PPE, arc flash clothing and equipment, you’ll want the design to be more comfortable and easier to use than ever before. If electrical workers feel comfortable with what they’re wearing, they are more likely to comply with your company’s PPE policies.
8. Is it important to enforce PPE policies?
PPE policies must be discussed on a regular basis to ensure that employees understand the importance of wearing the correct PPE and also the consequences of not wearing PPE. Unfortunately, it is human nature to try to get by without wearing the correct PPE. Because it only takes one time to make that crucial mistake, it is so important to remind workers throughout the year the consequences of not wearing PPE in your company.
9. Should I include Arc Flash PPE in my electrical safety program?
Because there can be a lot of confusion on arc flash protection, it’s very important to spell out in detail how to select the appropriate arc flash PPE and how to determine arc flash boundaries in your electrical safety program. The employer is responsible for providing arc flash protection gear, and the employee is responsible for wearing and maintaining that arc flash protection. The selection of the appropriate arc flash protection is imperative, requiring training to qualified persons helping in that decision-making process.
10. Do I need to wear arc flash protection every time I do electrical work?
It is important to understand that just because there is an electrical shock hazard present, it doesn’t mean there won’t be an arc flash hazard present as well. That is why it’s very important to complete an arc flash hazard assessment on your electrical equipment. There are two methods that can be used to determine what the appropriate arc flash PPE should be. A table method has been provided in the NFPA 70 E Standard to help determine if an arc flash hazard exists, and then what appropriate PPE should be worn. The problem with this method is that it’s based on a set of electrical parameters that may or may not fit your specific equipment. The only true way to determine if an arc flash hazard is present, and at what level, is by completing an incident energy analysis on your equipment. This type of analysis is an engineering study that is completed by collecting the correct electrical data and plugging it into a computer program.
About David Weszely:
Safety and Training Manager at Lewellyn Technology has been with the company for 5 years. He provides vision, leadership, safety training and technical expertise in areas of workplace safety including electrical safety program development. He also advises management on loss control and risk reduction strategies.