PaintSquare.com
      | Connect Follow us on Twitter Like us on Facebook
About | Subscribe | Advertise
  

 


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)

 
   

Binks/DeVilbiss
Built for Tough Jobs

From Epoxies to Urethanes to other high solid coatings, the new Binks Airless 75 delivers a great finish using an ergonomic design. Visit binks.com for more information.


Axxiom Manufacturing
Revolutionary Units

By integrating Schmidt's Aftercoolers with our blast pots, these systems remove moisture from air and minimize equipment footprint on jobsite.
Call 1-800-231-2085


HoldTight Solutions Inc.
NO FLASH RUST -
NO CONTAMINANTS

Our HoldTight®102 salt remover & flash rust preventer prevents flash
rust by removing surface contaminants. It has no equal; only wannabees.
Contact us for your
nearest distributor.
(800) 319.8802 sales@holdtight.com


Clemco Industries Corp.
Powerful Protection in a Small Package

Mounts inside blast helmet, alerts operator to dangerous breathing-air condition by audible, visual, and vibratory alarms. Easily calibrated, battery operated.


Blastox/The TDJ Group, Inc.
Blastox - One Step
Lead Abatement

Don't waste money on added labor steps with other methods. Don't mix, meter or apply at the job-site. Avoid strict hazardous waste rules.
Let your painters paint


Commercial Sand Blasting & Painting Ltd.
Reliable Service & Superior Workmanship

We’re ready to meet any of your protective coating and lining needs. We can work on your site or in our facilities, with large shops (60,000 sq ft), 40 acres of yard space, and cranes and forklifts on site.


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


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

Join SSPC and Enhance
Your Career !


Absolute Equipment/Grand Rental Station
Portable Power from Absolute Equipment

•Compressors
•Lighting Systems
•Generators
•Light Compaction
Sales • Rental • Service
Call 1-866-931-6655
Over a century of
providing excellence.

 
 
 
Technology Publishing

The Technology Publishing Network

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

 
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 2000-2015, 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