Yes, using safety equipment can help prevent injury or death -- but improper maintenance and storage of your PPE can give you a false sense of security.
Did you know that cleaning your rubber gloves incorrectly or folding rubber insulating sleeves for storage can increase the risk of accidental death by electrocution? Electrocution is not unusual in the construction industry. In fact, it causes 17% of job-related deaths, according to a 1996 OSHA directive. Even relatively low voltages can be fatal. The table, below, lists the effects of various 60 Hz currents passing from hand to foot for one second.
To protect yourself when working on or near energized parts, you should use personal protective equipment (PPE), including insulated rubber gloves, rubber sleeves, and protective apparel. Although not considered PPE, the use and care of rubber blankets have many similarities. More importantly, you should know how to store and test these safety products so they will continue to provide protection. Let's get into the details.
Rubber insulating gloves. Although caring for your gloves may seem like common sense, it's important to select the right size as well as clean, store, and inspect them properly.
Ordering. How do you select the proper size glove? Wrap a tape measure made of limp cloth around your hand at its palm, as you see in the photo, right. For Class 0 (1000V) and Class 00 (500V) gloves, you should order exactly (to the half inch) what the tape measure shows. For example, if you measure 8 in., you should order size 8 gloves. For Class 2 (20kV) gloves, add a half-inch to your measurement to allow for dexterity, ordering size 8 and one half
Storing. You should store rubber-insulated gloves and sleeves in a cool dark area; nowhere near steam pipes, radiators, or other sources of heat. Do not store them in the same room where electrical testing is done. If you're storing your gloves in glove bags, make sure you place the gauntlet end in the bottom of the bag, and hang the bag from a peg.
If you're storing them inside boxes or tool bags, do not place anything on top of them that would distort their shape. Do not wear or store your gloves inside-out. Also, do not leave the protector (leather) glove inside the rubber glove.
Cleaning. You can wash your rubber gloves by hand or in a washing machine to remove dirt. Use tap water and mild soap or mild non-bleaching detergent. After washing, rinse them in clear water and dry thoroughly at an air temperature not exceeding 150DegrF.
If your gloves come in contact with transformer oils, inhibitors, or other petroleum-based products, make sure you clean them with a manufacturer-approved liquid cleaner. Then, wipe with a clean dry cloth.
Inspection and testing. Make sure you air-test your rubber gloves before each use or if you suspect there is damage. You should also roll the gloves gently between your hands to expose defects and any imbedded materials. If you find any defects, do not use your gloves until you've electrically tested them.
You should base the interval between date of issue and electrical retests on your work practices and test experience. But, this interval should not exceed six months. If no one electrically tested your gloves within the previous 12 months and you haven't used them in that same interval, don't use them. Instead, have them retested. You can verify the testing date by the stamp on the gloves themselves.
Rubber insulating sleeves. Just like rubber gloves, you must follow specific guidelines to maximize safety when using insulating sleeves.
Storing. Never store sleeves inside out. Instead, store them with inserts still inside. If you must return sleeves to the field immediately following testing, you can roll them lengthwise and place them in a tube-shaped bag, or place them flat in storage bags with the inserts in place to prevent wrinkling.
• Do not fold or roll the wrist-end to the sleeve's shoulder tab.
• Do not store them in the direct rays of the sun or forced hot air.
• Do not hang sleeves by the shoulder straps or harness.
Inspection and testing. Make sure you carefully inspect the inner and outer surfaces of sleeves before using them to locate pinholes, cuts, scratches, aging, ozone checking, corona cutting, embedded foreign material, or other mechanical injuries. Stretching or rolling the rubber between the fingers will help you reveal defects.
Cleaning. You should follow the same cleaning and testing guidelines as noted for rubber gloves, except that testing should not exceed 12 months, instead of the six-month requirement for rubber insulating gloves.
Protective apparel. This apparel is vital in many situations and environments. In fact, OSHA requires each employer to assess the potential hazards in the work environment and determine the appropriate clothing materials using ASTM PS57-97. OSHA CFR 1910.269 "prohibits clothing, that when exposed to electrical arcs, could increase the extent of injury that would be sustained by the employee."
Acceptable flame-resistant (FR) materials are INDURA (100% cotton), NOMEX (5% Kevlar fibers), and PBI Kevlar (60% Kevlar and 40% PBI). Prohibited fabrics and fibers (when used alone) are acetate, nylon, polyester, and rayon.
That said, how do you maintain and store your FR clothing and arc hood? It's simple. If the clothing is dirty, wash them with warm water, use a cool rinse, and warm tumble dry. Do not use chlorine bleach or detergents containing chlorine bleach. The wash water and dryer air temperature should not exceed 140 DegrF. If your arc hood is dirty, remove its viewing window and launder it as described above.
Clean flash face shields and hood windows by washing them with warm water, rinsing, and drying them off with a soft towel.
Rubber blankets. Finally, make sure you don't overlook the proper safety procedures for rubber blanket use. Following a few simple rules will lengthen the life of your equipment and increase your safety.
Storing. Make sure you store these blankets wrinkle-free, either by hanging on pegs using their eyelets for suspension, or rolling them in the cartons or containers in which you received them. Before doing so, make sure you clean off all petroleum-based products and foreign substances.
• Do not fold blankets or place any objects on top of them.
• Do not store them in the direct rays of the sun or where hot air can blow on them.
Inspection. You should make a visual inspection of blankets in the field, with a frequency of at least once every six months. If a visual inspection causes you to suspect the electrical integrity of a blanket, make sure you have it electrically tested before reissuing it for service. Base the interval between date of issue and retest on work practices and test experience; not exceeding one year.
Use. Do not leave blankets on energized primary conductors beyond the end of your workday. Also, remember never to leave them under fiber or plastic line guards or insulator covers.
Do not wrap one blanket over another. This practice sets up a possible corona cutting condition and creates a false sense of security.
Do not use blankets having any of the following defects:
• Holes, tears, punctures, and cuts;
• Imbedded foreign objects;
• Swelling, softening, hardening, or stickiness;
• Corona cutting; or
• Severe ozone checking.
These guidelines show how important it is to take care of your PPE. Maintaining and storing it properly makes a big difference when it comes to safety. Just remember: Lengthening the life of your equipment could also lengthen your life.
Bird is the Chief Executive Officer of Certified Insulated Products, Beltsville, M.D.
