Using Dielectric and Electrical Hazard (EH) Shoes - Hugh Hoagland, Sr. Managing Partner, e-Hazard.com President, ArcWear.com
←
→
Page content transcription
If your browser does not render page correctly, please read the page content below
An e-Hazard.com White Paper
13113 Eastpoint Park Blvd.
Suite E
Louisville, KY 40223
502-716-7073
http://www.e-Hazard.com
Using Dielectric and Electrical Hazard (EH) Shoes
Hugh Hoagland, Sr. Managing Partner, e-Hazard.com
President, ArcWear.com
Updated 8/31/09Contents What Shoes do I Wear?
There are two basic names for shoes which
What Shoes do I Wear? 2 have some protection from electrical shock:
Hazard Assessment Guides 2 Dielectric and Electrical Hazard rated. The
differences between the standards even by
OSHA PPE General Guide 2
electrical specialists are not usually
NFPA 70E Guidelines 3 understood. Few guidelines exist on when
NFPA 70E Guideline Summary 4 and where to use the shoes in either
OSHA Guideline Summary 4 standard. This paper offers some assistance
on which standards relate to which shoes.
Shoe Standards 4
Which Standard Do I Choose? 5
Problems to Consider 6 Hazard Assessment Guides
Summary 6
OSHA PPE General Guide
According to 1910.136(a): "Each affected
employee shall wear protective footwear
when working in areas where there is a
danger of foot injuries due to falling or
rolling objects, or objects piercing the sole,
and where such employee's feet are exposed
to electrical hazards." Appendix B of
Subpart I identifies the following
occupations for which foot protection should
be routinely considered: shipping and
receiving clerks, stock clerks, carpenters,
electricians, machinists, mechanics and
repairers, plumbers, assemblers, drywall
installers and lathers, packers, wrappers,
craters, punch and stamping press operators,
sawyers, welders, laborers, freight handlers,
gardeners and grounds keepers, timber
cutting and logging workers, stock handlers
and warehouse laborers.
(http://www.osha.gov/pls/oshaweb/owadisp.
show_document?p_table=STANDARDS&p
_id=10120)
OSHA 29 CFR 1910.269 which applies to
transmission, distribution and generation of
electricity, cites ASTM F1117 shoes in the
standards document but gives no guidelines
as to when they are needed.
Updated 8/31/09http://www.osha.gov/pls/oshaweb/o NFPA 70E Guidelines
wadisp.show_document?p_id=9873 NFPA 70E attempts to give guidelines for
&p_table=STANDARDS using DI or EH shoes but it suffers from
some of the same issues as the OSHA
An OSHA interpretation letter from guides. It is better in the sense that it does
March 17, 1993 basically does not make use mandatory in a few cases but it is
“require” electrical trades to wear still unclear about the role, if any for EH
“safety toed shoes.” The letter states, shoes.
“One option you and your employer
may wish to consider is the purchase Electrical Hazard (EH) Shoes
of non-metallic safety footwear that Table 130.7(C)(8) Standards on Protective
provides both foot protection and is Equipment lists both ASTM F1117 and
non-conductive.” No later opinions F2413 under the footwear section but does
have been offered. not mention EH shoes. The ASTM F1117
standard is cited by the F2413 standard as
OSHA gives little guidance and the standard specification for DI shoes so
really only mentions the EH shoes in the citation of F2413 does not imply that EH
the general PPE guide for small shoes are required by NFPA 70E.
businesses. OSHA states, “Electrical
hazard, safety-toe shoes are Table 130.7(C)(10) Protective Clothing and
nonconductive and will prevent the Personal Protective Equipment (PPE) calls
wearers’ feet from completing an for all Hazard/Risk Categories (HRC) to
electrical circuit to the ground. These include “leather shoes” which in no case can
shoes can protect against open be dielectric shoes but “leather shoes” are
circuits of up to 600 volts in dry not equivalent to “EH” shoes.
conditions and should be used in
conjunction with other insulating 130.7(C)(13)(d) “Foot Protection. Heavy-
equipment and additional duty leather work shoes provide some arc
precautions to reduce the risk of a flash protection to the feet and shall be used
worker becoming a path for in all tasks in Hazard/Risk Category (HRC)
hazardous electrical energy. The 2 and higher and in all exposures greater
insulating protection of electrical than 4 cal/cm².” This would imply that DI
hazard, safety-toe shoes may be shoes alone are not acceptable but does not
compromised if the shoes become exclude EH shoes.
wet, the soles are worn through,
metal particles become embedded in Dielectric (DI) Shoes
the sole or heel, or workers touch “130.7(C)(7) Foot Protection. Where
conductive, grounded items. Note: insulated footwear is used as protection
Nonconductive footwear must not be against step and touch potential, dielectric
used in explosive or hazardous overshoes shall be required. Insulated soles
locations.” shall not be used as primary electrical
http://www.osha.gov/Publications/os protection.”
ha3151.pdf
130.5(E)(3) Dielectric overshoes are
required when performing “equipment
grounding near power lines.”
Updated 8/31/09Only dielectric footwear is listed in shoes but now shoes must meet ASTM
250.1 Maintenance Requirements for 2413-2005
Personal Safety and Protective
Equipment. ASTM F2413-2005
(http://www.astm.org/Standards/F2413.ht
320.8 Personal Protective m).
Equipment for Battery Rooms
requires protective overshoes but The ASTM F2413-05 standard covers
doesn’t indicate why they are used. minimum requirements for the design,
If they are for acid protection then performance, testing and classification of
they would need to meet an protective footwear. Footwear certified as
applicable part of F2413 but if for meeting ASTM F2413-05 must meet the
electrical hazards, they would need minimum requirements of Section 5.1
to meet ASTM F1117. “Impact Resistant Footwear” and Section
5.2 “Compression Resistant Footwear.”
In 310.5 (D)(2)(1) for protecting Additional sections have requirements of
employees working around specialty shoes such as metatarsal
electrolytic cells like in smelting protection, conductive protection, electric
operations, shoes are listed for “wet shock protection, static dissipative
service and if 130.7(C)(7) is protection and protection against punctures.
understood, the use of dielectric
shoes/overshoes or boots is required. ASTM specification must be marked with
the specific portion of the standard with
which it complies. One shoe of each pair
NFPA 70E Guideline Summary must be clearly and legibly marked (stitched
Dielectric shoes are required for wet in, stamped on, pressure sensitive label, etc.)
service and step potential hazards in on either the surface of the tongue, gusset,
any application and EH shoes are shaft or quarter lining.
optional, but leather is mandatory in
HRC 2-4. An example of ASTM style markings for
protective footwear is:
OSHA Guideline Summary
OSHA letters of interpretation ASTM F2413-05
present EH shoes positively but do M I/75/C/75/Mt75
not require them. In higher voltages PR
or higher risks (1910.269), OSHA EH
cites ASTM F1117 for dielectric
shoes NOT ANSI Z41 or ASTM First Line: ASTM F2413-05:
F2413. This means the protective footwear meets
the performance requirements of ASTM
F2413 issued in 2005.
Shoe Standards
Second Line : M I/75 C/75 Mt75:
ANSI Z41 M in this case means the footwear is
This was the old general safety shoe designed for a Male (F would be Female).
standard and used to include EH (I) denotes impact resistance followed by the
Updated 8/31/09impact resistance rating (75 or 50 in similar to the ASTM 2413 standard only
foot-pounds), (C) denotes more stringent in its leakage and voltage
compression resistance and the requirements. The CSA standard is also a
compression resistance rating (75 or “wet sole test.”
50 which correlates to 2500 pounds.
and 1750 pounds of compression ASTM F1116-03 (Reapproved 2008) is
respectively). (Mt) designates that the ASTM test method for dielectric shoes.
this shoe has metatarsal protection It has three different procedures which differ
and rating (75 or 50 foot-pounds). according to the section of the footwear
tested. (To purchase ASTM standards see
Third and Optional Fourth Line: http://www.astm.org/.)
PR EH.
The last two lines are used to ASTM F1117-03 (Reapproved 2008) is
identify footwear made to offer the specification for dielectric footwear and
protection from other specific types is a quite stringent standard. Only one boot
of hazards referenced in the standard. and overshoe currently meets the F1117-08
They designate conductive (Cd) specification.
properties, electrical insulation
properties (EH), static electricity The most important thing to be aware of is
dissipative (SD), puncture resistance that ASTM F2413 is a standard designed
(PR), chainsaw cut resistance (CS) primarily for impact and compression
and dielectric insulation (DI), if protection. Some dielectric shoes cannot
applicable. The last line is only used pass the compression portion of that
when more than three sections apply. standard because many are designed as
overshoes and don't have a steel toe, but the
Electrical Hazard (EH) footwear is overshoes can be worn with compression
manufactured with non-conductive resistant shoes if needed.
electrical shock resistant soles and
heels. The outsole can provide a Note: Steel toes have never been shown to
secondary electrical shock resistance conduct electricity as long as the toe is still
protection to the wearer against the covered with the shoe material.
hazards from an incidental contact
with energized electrical circuits or ASTM F-1117 refers to the boots and
parts. Testing ensures the materials overshoes as "supplementary protection"
are capable of withstanding 14,000 v since the shoes have no “in-use” standard.
at 60 Hz for one minute with no In-use standards normally require re-testing
current flow or leakage current in so shoes should never be relied on as
excess of 3.0 mA, under dry primary protection. An in-use standard is not
conditions. (This is NOT usually planned at the current time by the ASTM
acceptable for wet service or higher F18 committee.
voltages.). ASTM 2413 cites ASTM
F1117 for dielectric shoes.
Which Standard Do I Choose?
CAN/CSA-Zl95-M92 Section 4.3 First, choose the protection level or specific
(http://www.csa.ca ) standard you need: Dielectric or Electrical
CAN/CSA-Zl95-M92 Section 4.3 is
Updated 8/31/09Hazard levels. Second, choose the inspections and replacement when any sign
standard ASTM F1117, ASTM of excessive wear exists.
F2413 or CSA Z41,
PVC boots weigh up to 50 percent Summary
less than the rubber version, but do With OSHA early documents falling on the
not currently meet the ASTM side of EH shoes for electrical work,
standard. companies would do well to consider them
for all electrical workers and other workers
Third, look into the unique hazards exposed to electrical hazards or damp
of the work environment. The higher locations. These shoes rarely add more
the overshoe, the less likely there than five USD to the cost of the shoe and
will be water or grass or other they have been known to save lives. They
energized materials contacting the should be considered for low voltage
worker. Also, look closely at the heel (You can also read
