ASTM F1236-23

Standard Guide for Visual Inspection of Electrical Protective Rubber Products

SIGNIFICANCE AND USE
4.1 This guide provides inspection methods and techniques that may be used to examine electrical protective rubber products for irregularities. The methods have applications in manufacturing facilities, testing laboratories, and in the field where the products are used.  
4.2 This guide also contains photographs that illustrate the descriptions of terms listed in Section 3 and in Definitions F819.
SCOPE
1.1 The purpose of this guide is to present methods and techniques for the visual inspection of electrical protective rubber products. This guide also includes descriptions and photographs of irregularities found in these products.  
Note 1: It is not the purpose of this guide to establish the acceptance level of any irregularity described herein. That shall be established by the standard for each product.  
1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 30-Apr-2023
• ICS: 29.035.20 - Plastics and rubber insulating materials
• Technical Committee: F18 - Electrical Protective Equipment for Workers
• Drafting Committee: F18.60 - Terminology

Relations

• Refers: ASTM F496-23 - Standard Specification for In-Service Care of Insulating Gloves and Sleeves
• Effective Date: 01-Dec-2023
• Refers: ASTM F478-14a(2023) - Standard Specification for In-Service Care of Insulating Line Hose and Covers
• Effective Date: 01-Sep-2023
• Refers: ASTM F496-20 - Standard Specification for In-Service Care of Insulating Gloves and Sleeves
• Effective Date: 01-Jan-2020
• Refers: ASTM F478-14a(2019) - Standard Specification for In-Service Care of Insulating Line Hose and Covers
• Effective Date: 01-Apr-2019
• Refers: ASTM F496-14a - Standard Specification for In-Service Care of Insulating Gloves and Sleeves
• Effective Date: 01-Nov-2014
• Refers: ASTM F478-14a - Standard Specification for In-Service Care of Insulating Line Hose and Covers
• Effective Date: 01-Nov-2014
• Refers: ASTM F496-14 - Standard Specification for In-Service Care of Insulating Gloves and Sleeves
• Effective Date: 01-Apr-2014
• Refers: ASTM F478-14 - Standard Specification for In-Service Care of Insulating Line Hose and Covers
• Effective Date: 01-Apr-2014
• Refers: ASTM F479-06(2011) - Standard Specification for In-Service Care of Insulating Blankets
• Effective Date: 01-Dec-2011
• Refers: ASTM F819-10 - Standard Terminology Relating to Electrical Protective Equipment for Workers
• Effective Date: 01-Apr-2010
• Refers: ASTM F478-09 - Standard Specification for In-Service Care of Insulating Line Hose and Covers
• Effective Date: 01-Oct-2009
• Refers: ASTM F496-08 - Standard Specification for In-Service Care of Insulating Gloves and Sleeves
• Effective Date: 01-Oct-2008
• Refers: ASTM F819-08 - Standard Terminology Relating to Electrical Protective Equipment for Workers
• Effective Date: 15-May-2008
• Refers: ASTM F478-92(2007) - Standard Specification for In-Service Care of Insulating Line Hose and Covers
• Effective Date: 01-Jun-2007
• Refers: ASTM F819-06 - Standard Terminology Relating to Electrical Protective Equipment for Workers
• Effective Date: 15-Nov-2006

Overview

ASTM F1236-23: Standard Guide for Visual Inspection of Electrical Protective Rubber Products provides comprehensive guidance on the visual inspection of rubber-based electrical protective equipment. Developed by ASTM International, this standard outlines effective inspection methods, techniques, and terminology for detecting irregularities in products such as insulating gloves, sleeves, blankets, line hoses, and covers. The guide serves as a practical resource for manufacturers, testing laboratories, and field personnel to ensure worker safety and product reliability.

Key Topics

• Inspection Methods

  • Procedures for visually inspecting the surfaces of rubber insulating products, including gloves, sleeves, blankets, and hoses.
  • Techniques such as rolling, inflation, and proper lighting to reveal surface defects.
  • Handling directions for thorough coverage without damaging the products.

• Identification of Irregularities

  • Detailed descriptions of common irregularities encountered in electrical protective rubber products, including:
    • Abrasions, scratches, nicks, cuts, and tears
    • Age cracks and ozone cracks
    • Punctures, pits, and soft spots
    • Chemical bloom, color splash, and glove discoloration
    • Embedded foreign matter and mold marks
  • Photographic examples provided within the standard for clear identification.

• Terminology and Definitions

  • Consistent vocabulary to describe surface conditions, aiding clear communication among technicians, manufacturers, and safety professionals.
  • Reference to related ASTM definitions (see ASTM F819) for comprehensive understanding.

• Safety and Best Practices

  • Emphasis on cleaning products prior to inspection.
  • Proper use of lighting (minimum 200 fc) to maximize visibility of defects.
  • Safe manual or mechanical inflation techniques for detecting punctures or small holes in gloves and sleeves.
  • Guidance on not over-inflating or over-expanding rubber products, adhering to product-specific safety limits.

• Scope and Limitations

  • The guide does not define acceptance or rejection criteria for irregularities; acceptance standards are set by the specific product specification.

Applications

The ASTM F1236-23 visual inspection standard is widely applied in:

• Manufacturing: Quality control and assurance during and after production of electrical protective equipment.
• Testing Laboratories: Formal inspection protocols to validate the fitness and reliability of protective rubber goods before distribution or use.
• Field Use and In-Service Inspection: Routine and periodic assessments by utility workers, electricians, and safety professionals to detect wear and damage that may compromise protection.

By following this guide, organizations can increase safety, ensure regulatory compliance, and extend the service life of electrical protective rubber products. Accurate identification and documentation of surface irregularities help prevent equipment failure and protect workers from electrical hazards.

Related Standards

• ASTM F478: Specification for In-Service Care of Insulating Line Hose and Covers
• ASTM F479: Specification for In-Service Care of Insulating Blankets
• ASTM F496: Specification for In-Service Care of Insulating Gloves and Sleeves
• ASTM F819: Terminology Relating to Electrical Protective Equipment for Workers

These related ASTM standards complement F1236-23 by providing specific requirements on the care, maintenance, and terminology of rubber insulating equipment, supporting a comprehensive safety management system.

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Keywords: ASTM F1236-23, rubber electrical protective equipment, visual inspection, electrical safety, insulating gloves, line hose, dielectric rubber, field inspection, safety standards, irregularity detection, ASTM standards.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: F1236 − 23
Standard Guide for
Visual Inspection of Electrical Protective Rubber Products
This standard is issued under the fixed designation F1236; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 3. Terminology
1.1 The purpose of this guide is to present methods and 3.1 Definitions of Terms Specific to This Standard:
techniques for the visual inspection of electrical protective
3.1.1 abrasions and scratches—surface damage that nor-
rubber products. This guide also includes descriptions and
mally occurs when a product makes contact with an abrasive
photographs of irregularities found in these products.
surface (see Fig. 1 and Fig. 2).
NOTE 1—It is not the purpose of this guide to establish the acceptance
3.1.1.1 Discussion—Scuff-like damage can also occur from
level of any irregularity described herein. That shall be established by the
a brush contact with a hot object such as a soldering iron. This
standard for each product.
can sometimes look like the graining on leather.
1.2 The values stated in inch-pound units are to be regarded
3.1.2 age cracks—surface cracks that may look like the
as standard. The values given in parentheses are mathematical
crazing of glazed ceramics and become progressively worse
conversions to SI units that are provided for information only
with time (see Fig. 3).
and are not considered standard.
3.1.2.1 Discussion—It is a slow oxidation process caused by
1.3 This standard does not purport to address all of the
exposure to sunlight (or other environmental conditions) and
safety concerns, if any, associated with its use. It is the
starts in areas of the rubber that are under stress; see 3.1.14 for
responsibility of the user of this standard to establish appro-
ozone cracks damage.
priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use. 3.1.3 breakdown—the electrical discharge or arc occurring
1.4 This international standard was developed in accor-
between the electrodes and through the equipment being tested
dance with internationally recognized principles on standard- (see Figs. 4-6).
ization established in the Decision on Principles for the
3.1.4 chemical bloom—a white or yellowish discoloration
Development of International Standards, Guides and Recom-
on the surface of a rubber product caused by the migration to
mendations issued by the World Trade Organization Technical
the surface of chemical additives used in the manufacturing
Barriers to Trade (TBT) Committee.
process of the finished product (see Fig. 7), caused by the
natural aging process.
2. Referenced Documents
2.1 ASTM Standards:
3.1.4.1 Discussion—Not to be confused with 3.1.10 glove
F478 Specification for In-Service Care of Insulating Line discoloration.
Hose and Covers
3.1.5 color splash—a spot or blotch on the surface of a
F479 Specification for In-Service Care of Insulating Blan-
rubber product that occurred during the manufacturing process
kets
when a contrasting colored particle of unvulcanized rubber
F496 Specification for In-Service Care of Insulating Gloves
became embedded into the finished product (see Fig. 8).
and Sleeves
3.1.6 cuts—smooth incisions in the surface of the rubber
F819 Terminology Relating to Electrical Protective Equip-
that are usually caused by a sharp-edged object that can
ment for Workers
increase in size when they are placed under strain (see Fig. 9).
3.1.7 depressions or indentations—a shallow recess in the
This guide is under the jurisdiction of ASTM Committee F18 on Electrical
surface of the rubber that exhibits a thinner rubber thickness at
Protective Equipment for Workers and is the direct responsibility of Subcommittee
F18.60 on Terminology.
the bottom of the depression than in the surrounding areas (see
Current edition approved May 1, 2023. Published May 2023. Originally
Fig. 10).
approved in 1989. Last previous edition approved in 2019 as F1236 – 19. DOI:
10.1520/F1236-23.
3.1.8 embedded foreign matter—a particle of non-rubber
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
material that has been molded into the finished product and
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
may appear as a bump when the rubber is stretched (see Fig.
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. 11).
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F1236 − 23
3.1.13 nicks, snags, or scratches—angular tears, notches, or
chip-like injuries in the surface of the rubber that have been
caused by barbed wire, sharp pointed tools, staples, splinters or
similar sharp edged hazards (see Fig. 2, Fig. 21, and Fig. 22).
3.1.14 ozone cracks—a series of interlacing cracks that may
start at stress points and quickly worsen as a result of rapid
oxidation in a highly concentrated ozone atmosphere usually
produced by electrical arcing (see Figs. 23-26).
3.1.15 parting line or flash line—a ridge of rubber left on
finished products occurring at mold joints during the manufac-
turing process.
3.1.16 pitting—a depression in the surface of the rubber that
may have been created by the rupturing of an air bubble at or
near the surface of the rubber during the manufacturing process
(see Fig. 27).
3.1.17 protuberance—bulge or swelling that protrudes
above the surface of the rubber that may have occurred during
the manufacturing process (see Fig. 28).
FIG. 1 Abrasion
3.1.18 puncture—penetration by a sharp object through the
entire thickness of the rubber product (see Fig. 29).
3.1.19 repair marks—an area on the surface of the finished
product that has a different texture due to the repair or
reworking of an irregularity in the mold or form (see Fig. 30).
3.1.20 runs—raised flow marks that may occur on the
fingers of rubber gloves during the dipping process (see Fig.
31).
3.1.21 skin breaks—cavities in the surface of the rubber
with filmy ragged edges and smooth interior surfaces that are
normally caused by embedded dirt specks during the manufac-
turing process.
3.1.22 soft spots—surface areas of the rubber that have
become soft and sometimes tacky as a result of exposure to
heat, oils, or chemical solvents (see Fig. 32).
3.1.23 tears—a separation of the rubber through its entire
thickness, usually at an edge, that has been created by a
forceful pulling apart of the rubber (see Fig. 33 and Fig. 34).
3.1.24 tracking—the formation of a carbonized path on the
surface of a solid insulating medium, resulting from excessive
current leakage over the surface (see Figs. 35-37).
FIG. 2 Scratches
4. Significance and Use
3.1.9 form marks—a raised or indented section on the
4.1 This guide provides inspection methods and techniques
surface of the rubber that was caused by an irregularity in the
that may be used to examine electrical protective rubber
form.
products for irregularities. The methods have applications in
manufacturing facilities, testing laboratories, and in the field
3.1.10 glove discoloration—a non-harmful surface discolor-
where the products are used.
ation on a rubber insulating glove caused by the leaching of the
tanning chemicals in leather protectors when protectors are left
4.2 This guide also contains photographs that illustrate the
on the rubber insulating glove for an extended time; this is
descriptions of terms listed in Section 3 and in Definitions
accelerated when the protectors are wet (see Figs. 12-14).
F819.
3.1.11 hard spot—a hardened area on the rubber surface that
5. Inspection Methods
is usually caused by exposure to high heat or chemical attack
(see Figs. 15-18).
5.1 Rolling:
3.1.12 mold marks—a raised or indented section on the 5.1.1 Inspect glove and sleeve surface areas by gently
surface of the rubber that was caused by an irregularity in the rolling their entire outside and inside surface areas between the
mold (see Fig. 19 and Fig. 20). hands. This technique requires gently squeezing together the
F1236 − 23
FIG. 3 Age Cracks
FIG. 5 Breakdown (Dielectric Failure Blanket: Front)
FIG. 4 Breakdown (Dielectric Failure Blanket: Back)
up. Unroll the bl
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: F1236 − 19 F1236 − 23
Standard Guide for
Visual Inspection of Electrical Protective Rubber Products
This standard is issued under the fixed designation F1236; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 The purpose of this guide is to present methods and techniques for the visual inspection of electrical protective rubber
products. This guide also includes descriptions and photographs of irregularities found in these products.
NOTE 1—It is not the purpose of this guide to establish the acceptance level of any irregularity described herein. That shall be established by the standard
for each product.
1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical
conversions to SI units that are provided for information only and are not considered standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
1.4 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
F478 Specification for In-Service Care of Insulating Line Hose and Covers
F479 Specification for In-Service Care of Insulating Blankets
F496 Specification for In-Service Care of Insulating Gloves and Sleeves
F819 Terminology Relating to Electrical Protective Equipment for Workers
3. Terminology
3.1 Definitions of Terms Specific to This Standard:
3.1.1 abrasions and scratches—surface damage that normally occurs when a product makes contact with an abrasive surface (see
Fig. 1 and Fig. 2).
3.1.1.1 Discussion—
Scuff-like damage can also occur from a brush contact with a hot object such as a soldering iron. This can sometimes look like
the graining on leather.
This guide is under the jurisdiction of ASTM Committee F18 on Electrical Protective Equipment for Workers and is the direct responsibility of Subcommittee F18.60
on Terminology.
Current edition approved May 1, 2019May 1, 2023. Published June 2019May 2023. Originally approved in 1989. Last previous edition approved in 20182019 as
F1236 – 18.F1236 – 19. DOI: 10.1520/F1236-19.10.1520/F1236-23.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F1236 − 23
FIG. 1 Abrasion
FIG. 2 Scratches
3.1.2 age cracks—surface cracks that may look like the crazing of glazed ceramics and become progressively worse with time (see
Fig. 3).
3.1.2.1 Discussion—
It is a slow oxidation process caused by exposure to sunlight (or other environmental conditions) and starts in areas of the rubber
that are under stress; see 3.1.14 for ozone cracks damage.
3.1.3 breakdown—the electrical discharge or arc occurring between the electrodes and through the equipment being tested (see
Figs. 4-6).
3.1.4 chemical bloom—a white or yellowish discoloration on the surface of a rubber product caused by the migration to the surface
of chemical additives used in the manufacturing process of the finished product (see Fig. 7), caused by the natural aging process.
3.1.4.1 Discussion—
Not to be confused with 3.1.10 glove discoloration.
F1236 − 23
FIG. 3 Age Cracks
FIG. 4 Breakdown (Dielectric Failure Blanket: Back)
3.1.5 color splash—a spot or blotch on the surface of a rubber product that occurred during the manufacturing process when a
contrasting colored particle of unvulcanized rubber became embedded into the finished product (see Fig. 8).
3.1.6 cuts—smooth incisions in the surface of the rubber that are usually caused by a sharp-edged object that can increase in size
when they are placed under strain (see Fig. 9).
3.1.7 depressions or indentations—a shallow recess in the surface of the rubber that exhibits a thinner rubber thickness at the
bottom of the depression than in the surrounding areas (see Fig. 10).
3.1.8 embedded foreign matter—a particle of non-rubber material that has been molded into the finished product and may appear
as a bump when the rubber is stretched (see Fig. 11).
3.1.9 form marks—a raised or indented section on the surface of the rubber that was caused by an irregularity in the form.
F1236 − 23
FIG. 5 Breakdown (Dielectric Failure Blanket: Front)
FIG. 6 Breakdown (Dielectric Failure)
FIG. 7 Chemical Bloom
F1236 − 23
FIG. 8 Color Splash
FIG. 9 Cuts
3.1.10 glove discoloration—a non-harmful surface discoloration on a rubber insulating glove caused by the leaching of the tanning
chemicals in leather protectors when protectors are left on the rubber insulating glove for an extended time; this is accelerated when
the protectors are wet (see Figs. 12-14).
3.1.11 hard spot—a hardened area on the rubber surface that is usually caused by exposure to high heat or chemical attack (see
Figs. 15-18).
F1236 − 23
FIG. 10 Depressions
FIG. 11 Foreign Matter
FIG. 12 Glove Discoloration
3.1.12 mold marks—a raised or indented section on the surface of the rubber that was caused by an irregularity in the mold (see
Fig. 19 and Fig. 20).
3.1.13 nicks, snags, or scratches—angular tears, notches, or chip-like injuries in the surface of the rubber that have been caused
by barbed wire, sharp pointed tools, staples, splinters or similar sharp edged hazards (see Fig. 2, Fig. 21, and Fig. 22).
F1236 − 23
FIG. 13 Glove Discoloration
FIG. 14 Glove Discoloration
3.1.14 ozone cracks—a series of interlacing cracks that may start at stress points and quickly worsen as a result of rapid oxidation
in a highly concentrated ozone atmosphere usually produced by electrical arcing (see Figs. 23-26).
3.1.15 parting line or flash line—a ridge of rubber left on finished products occurring at mold joints during the manufacturing
process.
3.1.16 pitting—a pit-like depression in the surface of the rubber that may have been created by the rupturing of an air bubble at
or near the surface of the rubber during the manufacturing process (see Fig. 27).
3.1.17 protuberance—bulge or swelling that protrudes above the surface of the rubber that may have occurred during the
manufacturing process (see Fig. 28).
3.1.18 puncture—penetration by a sharp object through the entire thickness of the rubber product (see Fig. 29).
F1236 − 23
FIG. 15 Hard Spot
FIG. 16 Hard Spot
3.1.19 repair marks—an area on the surface of the finished product that has a different texture due to the repair or reworking of
an irregularity in the mold or form (see Fig. 30).
3.1.20 runs—raised flow marks that may occur on the fingers of rubber gloves during the dipping process.process (see Fig. 31).
3.1.21 skin breaks—cavities in the surface of the rubber with filmy ragged edges and smooth interior surfaces that are normally
caused by embedded dirt specks during the manufacturing process.
3.1.22 soft spots—surface areas of the rubber that have become soft and sometimes tacky as a result of exposure to heat, oils, or
chemical solvents (see Fig. 3132).
3.1.23 tears—a separation of the rubber through its entire thickness, usually at an edge, that has been created by a forceful pulling
apart of the rubber (see Fig. 3233 and Fig. 3334).
3.1.24 tracking—the formation of a carbonized path on the surface of a solid insulating medium, resulting from excessive current
leakage over the surface (see Figs. 34-35-3637).
F1236 − 23
FIG. 17 Hard Spot
FIG. 18 Hard Spot
F1236 − 23
FIG. 19 Mold Marks
FIG. 20 Mold Marks
FIG
...