ASTM D7868-21

Standard Practice for Determining the Dry Fall (Fog) Properties of Protective Coatings

SIGNIFICANCE AND USE
5.1 Attachment of overspray particles to vehicles and other surfaces not intended to be coated can result in property damage and insurance claims. Dry fall coatings are formulated such that overspray particles dry as they move through the air, and before they land on horizontal surfaces. These particles can then be brushed off, vacuumed or washed from the surfaces with no damage. This practice can be used to evaluate the dry fall properties of coatings prior to large scale use. The practice can also be used to evaluate whether the coating(s) possess the same dry fall properties when the fallout collects on surfaces with an elevated temperature.
SCOPE
1.1 This practice covers a procedure for qualitatively evaluating the dry fall properties of coatings. The establishment of the test environment and the evaluation procedures are described.  
1.2 This practice uses panels containing an automotive finish since these types of surfaces are often the primary concern relating to overspray damage. Panels coated with other systems may be used as collection surfaces when they are deemed to be more representative.  
1.3 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.  
1.4 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.  
1.5 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: 31-Oct-2021
• ICS: 87.040 - Paints and varnishes
• Technical Committee: D01 - Paint and Related Coatings, Materials, and Applications
• Drafting Committee: D01.46 - Industrial Protective Coatings

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: D7868 − 21
Standard Practice for
Determining the Dry Fall (Fog) Properties of Protective
1
Coatings
This standard is issued under the fixed designation D7868; 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 This practice covers a procedure for qualitatively evalu- 3.1 Definitions:
ating the dry fall properties of coatings. The establishment of 3.1.1 dry fall/fog coating, n—an interior or exterior coating
the test environment and the evaluation procedures are de- specially formulated so that the fine particles of overspray dry
scribed. to a dust or powder during a free fall of a certain distance at
specific temperature and humidity ranges, and will not adhere
1.2 This practice uses panels containing an automotive
to surfaces on which the overspray is subsequently deposited.
finish since these types of surfaces are often the primary
concern relating to overspray damage. Panels coated with other
4. Summary of Practice
systems may be used as collection surfaces when they are
4.1 A structural frame is erected and enclosed unless a dry
deemed to be more representative.
fall/fog test chamber or laboratory space is pre-designated.
1.3 The values stated in inch-pound units are to be regarded
Spray targets are placed at the top, inside the enclosure. Four
as standard. The values given in parentheses are mathematical
steel panels coated with an automotive basecoat/clear coat
conversions to SI units that are provided for information only
system are placed on the enclosure floor to collect the dry fall.
and are not considered standard.
(Panels coated with other systems or uncoated panels, or both,
1.4 This standard does not purport to address all of the
can be used when they are deemed to be more representative.)
safety concerns, if any, associated with its use. It is the
A duplicate panel set is maintained at the prevailing air
responsibility of the user of this standard to establish appro-
temperature, while the other duplicate panel set is heated in
priate safety, health, and environmental practices and deter-
oven and placed inside the enclosure immediately prior to
mine the applicability of regulatory limitations prior to use.
atomizing the coating. The coating is atomized against the
1.5 This international standard was developed in accor-
targets at each of two distances and the panels are removed for
dance with internationally recognized principles on standard-
evaluation. Two of the coated steel panels remain at laboratory
ization established in the Decision on Principles for the
ambient conditions, while the “pre-heated” panels are returned
Development of International Standards, Guides and Recom-
to a laboratory oven.The heated and ambient coated panels are
mendations issued by the World Trade Organization Technical
cleaned and evaluated after 24-h for dry fall attachment.
Barriers to Trade (TBT) Committee.
5. Significance and Use
2. Referenced Documents
5.1 Attachment of overspray particles to vehicles and other
2
2.1 ASTM Standards:
surfaces not intended to be coated can result in property
D610 Practice for Evaluating Degree of Rusting on Painted
damage and insurance claims. Dry fall coatings are formulated
Steel Surfaces
such that overspray particles dry as they move through the air,
D5402 Practice for Assessing the Solvent Resistance of
andbeforetheylandonhorizontalsurfaces.Theseparticlescan
Organic Coatings Using Solvent Rubs
then be brushed off, vacuumed or washed from the surfaces
with no damage. This practice can be used to evaluate the dry
fall properties of coatings prior to large scale use. The practice
1
This practice is under the jurisdiction of ASTM Committee D01 on Paint and
can also be used to evaluate whether the coating(s) possess the
Related Coatings, Materials, and Applications and is the direct responsibility of
Subcommittee D01.46 on Industrial Protective Coatings.
same dry fall properties when the fallout collects on surfaces
Current edition approved Nov. 1, 2021. Published November 2021. Originally
with an elevated temperature.
approved in 2013. Last previous edition approved in 2017 as D7868 – 13 (2017).
DOI: 10.1520D7868-21.
6. Reagents
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
6.1 Commercially available Car Washing Concentrate.
Standards volume information, refer to the standard’s
...

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: D7868 − 13 (Reapproved 2017) D7868 − 21
Standard Practice for
Determining the Dry Fall (Fog) Properties of Protective
1
Coatings
This standard is issued under the fixed designation D7868; 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 This practice covers a procedure for qualitatively evaluating the dry fall properties of coatings. The establishment of the test
environment and the evaluation procedures are described.
1.2 This practice uses panels containing an automotive finish since these types of surfaces are often the primary concern relating
to overspray damage. Panels coated with other systems may be used as collection surfaces when they are deemed to be more
representative.
1.3 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.
1.4 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.
1.5 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
2.1 ASTM Standards:
D610 Practice for Evaluating Degree of Rusting on Painted Steel Surfaces
D5402 Practice for Assessing the Solvent Resistance of Organic Coatings Using Solvent Rubs
3. Terminology
3.1 Definitions:
3.1.1 dry/fall/fog dry fall/fog coating, n—an interior or exterior coating specially formulated so that the fine particles of overspray
dry to a dust or powder during a free fall of a certain distance at specific temperature and humidity ranges, and will not adhere
to surfaces on which the overspray is subsequently deposited.
1
This practice is under the jurisdiction of ASTM Committee D01 on Paint and Related Coatings, Materials, and Applications and is the direct responsibility of
Subcommittee D01.46 on Industrial Protective Coatings.
Current edition approved Dec. 1, 2017Nov. 1, 2021. Published December 2017November 2021. Originally approved in 2013. Last previous edition approved in 20132017
as D7868 – 13. 13 (2017). DOI: 10.1520D7868-13R17.10.1520D7868-21.
2
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
1

---------------------- Page: 1 ----------------------
D7868 − 21
4. Summary of Practice
4.1 A structural frame is erected and enclosed. enclosed unless a dry fall/fog test chamber or laboratory space is pre-designated.
Spray targets are placed at the top, inside the enclosure. Four steel panels coated with an automotive basecoat/clear coat system
are placed on the enclosure floor to collect the dry fall. (Panels coated with other systems or uncoated panels, or both, can be used
when they are deemed to be more representative.) A duplicate panel set is maintained at the prevailing air temperature, while the
other duplicate panel set is heated in oven and placed inside the enclosure immediately prior to atomizing the coating. The coating
is atomized against the targets at each of two distances and the panels are removed for evaluation. Two of the coated steel panels
remain at laboratory ambient conditions, while the “pre-heated” panels are returned to a laboratory oven. The heated and ambient
coated panels are cleaned and evaluated after 24-h for dry fall attachment.
5. Significance and Use
5.1 Attachment of overspray particles to vehicles and other surfaces not intended to be coated can result in property damage and
insurance claims. Dry fall coatings are formulated such that overspray particles dry as they move through the air, and before they
land
...