PaintSquare.com


The First Word in Protective & Marine Coatings

A Product of Technology Publishing / PaintSquare
JPCL | PaintSquare News | Durability + Design | Paint BidTracker


D4787 Standard Practice for Continuity Verification of Liquid or Sheet Linings Applied to Concrete Substrates

All Standards | ASTM Standards
Search Standards


Click to Purchase and Download this Standard or Test Method

Revision Date: April 01, 2013
Updated On: June 04, 2013
Editorial Change:
 
5.1 The electrical conductivity of concrete is primarily influenced by the presence of moisture. Other factors, which affect the electrical continuity of concrete structures, include the following: 5.1.1 Presence of metal rebars, 5.1.2 Cement content and type, 5.1.3 Aggregate types, 5.1.4 Admixtures, 5.1.5 Porosity within the concrete, 5.1.6 Above or below grade elevation, 5.1.7 Indoor or outdoor location, 5.1.8 Temperature and humidity, and 5.1.9 Age of concrete.

5.2 The electrical conductivity of concrete itself may be successfully used for high-voltage continuity testing of linings applied directly with no specific conductive underlayment installed. However, the voltage required to find a discontinuity may vary greatly from point to point on the structure. This variance may reduce the test reliability.

5.3 Although the most common conductive underlayments are liquid primers applied by trowel, roller, or spray, and which contain carbon or graphite fillers, others may take the form of the following: 5.3.1 Sheet-applied graphite veils, 5.3.2 Conductive polymers, 5.3.3 Conductive graphite fibers, 5.3.4 Conductive metallic fibers, and 5.3.5 Conductive metallic screening.

5.4 Liquid-applied conductive underlayments may be desirable as they can serve to address imperfections in the concrete surface and provide a better base for which to apply the lining.

5.5 This practice is intended for use only with new linings applied to concrete substrates. Inspecting a lining previously exposed to an immersion condition could result in damaging the lining or produce an erroneous detection of discontinuities due to permeation or moisture absorption of the lining. Deposits may also be present on the surface causing telegraphing. The use of a high voltage tester on a previously exposed lining is not recommended because of possible spark through which will damage an otherwise sound lining. A low voltage tester can be used but could produce erroneous readings. 5.6 The user may consider this practice when performance requirements of the lining in a specified chemical environment require assurance of a lining free of discontinuities.

5.7 Factors affecting the dielectric properties and test voltage shall be considered. Some factors are the curing time of liquid-applied linings; the possible presence of electrically conductive fillers or solvents, or both; the possible presence of air inclusions or voids; and the compatibility of conductive underlayments with the specified lining. 5.8 A pulsed dc high voltage may cause a lining to breakdown at a lower voltage than would be the case for a continuous dc voltage.

(Back to all Standards)

 
   

Safway Services
One Source. Every Solution.

The Safway Group is your source for multiservices. Painting, coating, insulation and more – all from the most trusted name in the industry.


CHLOR*RID International Inc.
Free Webinar

Learn about soluble salts, along with a discussion on allowable levels.
More information at
www.chlor-rid.com,

800-422-3217


International Paint LLC

International Paint Engineered Coatings

Learn about our solutions for:
  • Structural Steel
  • Piping & Equipment
  • Storage Tanks
  • Pressure Vessels
  • Secondary Containment


    SSPC: The Society for Protective Coatings
    http://www.sspc.org/

    Join SSPC and Enhance
    Your Career !


    Spider, a Division of SafeWorks, LLC
    Complete Suspended Access Solutions

    Need access? From platforms & hoists to rigging & fall protection, Spider leads the industry in rentals, sales & service. Call 877-774-3370 or click today.


    Novatek Corporation
    Dustless Coatings Removal

    Strip it, clean it, and profile it,
    all dust free! High production
    rates and Blast like finishes.
    Comply with new lead
    standards.


    Fischer Technology Inc.
    MP0R with rotating display screen

    View your coating thickness readings from any angle with rotating display screen. New graphic display with easy menu navigation. Click for Video
    Call 800-243-8417

  •  
     
     
    Technology Publishing

    The Technology Publishing Network

    The Journal of Protective Coatings & Linings (JPCL) PaintSquare
    Durability + Design Paint BidTracker JPCL Europe

     
    EXPLORE:      JPCL   |   PaintSquare News   |   Interact   |   Buying Guides   |   Webinars   |   Resources   |   Classifieds
    REGISTER AND SUBSCRIBE:      Free PaintSquare Registration   |   Subscribe to JPCL   |   Subscribe to PaintSquare News
    MORE:      About PaintSquare.com   |   Privacy policy   |   Terms & conditions   |   Site Map   |   Search   |   Contact Us
     

    © Copyright 2000-2014, Technology Publishing / PaintSquare, All rights reserved
    2100 Wharton Street, Suite 310, Pittsburgh PA 15203-1951; Tel 1-412-431-8300; Fax 1-412-431-5428; E-mail webmaster@paintsquare.com