Page 42 - Occupational Health & Safety, June 2017

ELECTRICAL SAFETY
ing glove for the task at hand and the level of electrical exposure. Rubber insulating gloves are typically manufactured in sizes 8-12, often in half sizes, and some manu- facturers also offer gloves as small as size 7 and as large as size 13. In addition, rubber insulating gloves are available in different cuff lengths of 11, 14, 16, and 18 inches, de- pending on the glove class. Rubber insulat- ing gloves are available in six specific volt- age classes (Class 00 to Class 4), and other rubber insulating products are available in different voltage classes, as well.
1.50 times their normal size. Listen for escaping air to detect holes. If a portable inflator is not available, use a rubber glove inspection tool or roll the glove cuff tightly to trap air inside. Then, apply pressure to areas of the glove to inspect for escaping air. Repeat the procedure again with the rubber gloves turned inside out.
Thoroughly inspect all rubber insulat- ing equipment prior to use.
Perform Electrical Testing for Con- tinued Compliance, Cost Savings Various ASTM Manufacturing and Ac- ceptance standards mandate the testing of the rubber insulating products by the manufacturer or supplier prior to the first delivery to the end user. Users also have the option of performing or requiring an ac- ceptance test upon receipt of the goods and prior to placing rubber insulating products into service. Once placed in service, there are periodic retest intervals specified in the following ASTM standards:
■ ASTM F496 Rubber Insulating Gloves –6 months (under very limited con- ditions this can increase to 9 months)
■ ASTM F496 Rubber Insulating Sleeves—12 months
■ ASTM F479 Rubber Insulating Blankets—12 months
■ ASTM F478 Line Hose & Covers— when field inspection or company policy warrant
These in-service retest intervals are the maximum permitted and in addition to the daily field care and inspection. It is quite common for users, including power utilities and contractors, to specify shorter intervals. However, do not place rubber in- sulating products into service unless they have been electrically tested within the pre- vious 12 months.
Rubber goods should be electrically tested at their rated test voltage using spe- cialized equipment designed to gradually increase the voltage to the desired test level. The dielectric test is two-fold: pass/fail on the ability to withstand the rated test volt- age and, for gloves, quantitative on the abil- ity to prevent electric current from pass- ing through the rubber goods above the maximum contained in the specifications. Products passing the inspection and test procedures can then be returned to service.
If you do not have the equipment re- quired to perform these electrical tests, there are independent testing facilities that
can perform the acceptance and in-service testing on behalf of end users. ASTM stan- dards recommend that the inspection and testing process include the following steps:
1. Check-in
2. Removing previous testing marking 3. Washing using cleaning agents that
will not degrade the insulating properties 4. Visual inspection of all services (in-
side and out)
5. Electrical test
6. Final inspection
7. Recordkeeping
8. Marking
9. Packing in appropriate containers
(“appropriate containers” means boxes, or similar sturdy packaging materials to pre- vent folding, creasing or similar loose stor- age that can cause stress on the rubber) for storage or shipment
When selecting a test lab for use, make sure that it is a NAIL-accredited test lab. NAIL stands for National Association of Independent Laboratories for Protective Equipment Testing (www.nail4pet.org). It incorporates the only Laboratory Accredi- tation for the electrical equipment test labs program in North America. NAIL- 4PET helps develop uniformity in test- ing and works in close association with ASTM International.
Conclusion
Nearly all industrial workplaces have a need for electrical safety; failure to comply can result in heavy fines, serious injuries, and even death. Fortunately, there are practices you can easily implement into your electri- cal safety program that prevent injuries, citations, penalties, and superfluous spend- ing. It starts with awareness of the need for electrical safety, utilizing visual inspection as the first line of defense for your electrical safety products and periodically re-testing rubber insulating equipment for continued confirmation of effectiveness.
Richard A. Rivkin is President and Chief Executive Officer of Saf-T-Gard Interna- tional, Inc., a privately held, family-owned and -operated global supplier of industrial safety products based in Northbrook, Ill. To learn more, visit www.saftgard.com or call 1-800-548-GARD (4273).
E-mail marketing@saftgard.com to re- quest your free rubber insulating products care and use poster, and use this tool to aid you in your daily inspections!
Class Color
Proof Test Voltage AC / DC
Max. Use Voltage AC / DC
00 Beige
2,500 / 10,000
500 / 750
0 Red
5,000 / 20,000
1,000 / 1,500
1 White
10,000 / 40,000
7,500 / 11,250
2 Yellow
20,000 / 50,000
17,000 / 25,500
3 Green
30,000 / 60,000
26,500 / 39,750
These are all AC voltages. The ASTM standards also include DC test and maxi- mum use voltages.
There is a significant margin of safety between the proof test voltages and the maximum working voltage. Gloves and other rubber insulating products must be permanently marked to indicate the volt- age class, and the gloves and sleeves must also have a color-coded label identifying the voltage class.
Verifying Product Integrity with Visual Inspection
OSHA and ASTM standards also require regular inspection of in-service electrical protective equipment in order to main- tain compliance and ensure the products’ safety and integrity when exposed to a wide range of voltages. Visually inspecting rubber gloves and sleeves identifies physi- cal, chemical, or ozone damage. Direct light is recommended because it enhances the ability to see surface imperfections on the rubber. Inflating the gloves with air or otherwise stretching the surface helps iden- tify age and ozone damage as well as other physical damage, such as snags, rope burns, deep cuts, and punctures.
Expand the gloves no more than 1.25-
38 Occupational Health & Safety | JUNE 2017
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