ASTM F1738-23

Standard Test Method for Determination of Deposition of Aerially Applied Oil Spill Dispersants

SIGNIFICANCE AND USE
3.1 The deposition of an aerially applied dispersant is defined as the amount of an aerially applied dispersant that contacts the surface; whereas, application dosage (frequently referred to as application rate) is the amount of material that is released per unit area by the delivery system. The units of deposition are litres per hectare or U.S. gallons per acre. The deposition may differ from the application dosage (volume of material per unit area) for many reasons, such as, the effects of wind on the spray and the evaporation of the dispersant after it has been released from the aircraft.  
3.2 This test method describes the measurement of the ability of a spray system to deposit a dispersant on oil. It is not intended that this test method be used at the time of a spill. These techniques are intended to determine the equipment performance during the development of new systems and after the repair or significant modification of a system.  
3.3 The data obtained from the use of this test method can be directly related to the deposition of dispersant on an oil slick, and thus can serve to determine both the dispersant deposition and the drop size.  
3.4 Surrogate deposition and drop size data can be used as a technical basis for the optimization of dispersant application equipment and its use.  
3.5 The choice of a dispersant surrogate may vary, typically water is chosen along with a marker dye.
SCOPE
1.1 This test method covers the measurement of the deposition of an aerially applied dispersant surrogate, typically dyed water, on the surface of the ground or water. The test method of obtaining these measurements is described, and the analysis of the results, in terms of dispersant use, is considered. There are a number of techniques that have been developed, and this test method outlines their application. These measurements can be used to confirm or verify the specifications of a given equipment set, its proper functioning, and use.  
1.2 This test method is applicable to systems used with helicopters or airplanes.  
1.3 This test method is one of four related to dispersant application systems. Guide F1413/F1413M covers design, Practice F1460/F1460M covers calibration, Test Method F1738 covers deposition, and Guide F1737/F1737M covers the use of the systems. Familiarity with all four standards is recommended.  
1.4 There are some exposure and occupational health concerns regarding the methods described. These are not discussed in this test method since they are a function of dispersant formulation. Anyone undertaking such experiments should consult the occupational health experts of the dispersant manufacturer regarding the precautions to be used.  
1.5 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.6 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.  
1.7 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: 28-Feb-2023
• ICS: 13.060.10 - Water of natural resources
• Technical Committee: F20 - Hazardous Substances and Oil Spill Response
• Drafting Committee: F20.13 - Treatment

Relations

• Refers: ASTM E1260-03(2020) - Standard Test Method for Determining Liquid Drop Size Characteristics in a Spray Using Optical Nonimaging Light-Scattering Instruments
• Effective Date: 01-Apr-2020
• Refers: ASTM E642-19 - Standard Practice for Determining Application Rates and Distribution Patterns from Aerial Application Equipment
• Effective Date: 01-Oct-2019
• Refers: ASTM F1737/F1737M-15 - Standard Guide for Use of Oil Spill Dispersant Application Equipment During Spill Response: Boom and Nozzle Systems
• Effective Date: 01-Mar-2015
• Refers: ASTM E1260-03(2015) - Standard Test Method for Determining Liquid Drop Size Characteristics in a Spray Using Optical Nonimaging Light-Scattering Instruments
• Effective Date: 01-Mar-2015
• Refers: ASTM E642-91(2014) - Standard Practice for Determining Application Rates and Distribution Patterns from Aerial Application Equipment
• Effective Date: 01-Oct-2014
• Refers: ASTM F1737/F1737M-10 - Standard Guide for Use of Oil Spill Dispersant Application Equipment During Spill Response: Boom and Nozzle Systems
• Effective Date: 01-Apr-2010
• Refers: ASTM E1260-03(2009) - Standard Test Method for Determining Liquid Drop Size Characteristics in a Spray Using Optical Nonimaging Light-Scattering Instruments
• Effective Date: 01-Nov-2009
• Refers: ASTM E642-91(2008) - Standard Practice for Determining Application Rates and Distribution Patterns from Aerial Application Equipment
• Effective Date: 01-Oct-2008
• Refers: ASTM E1260-03 - Standard Test Method for Determining Liquid Drop Size Characteristics in a Spray Using Optical Nonimaging Light-Scattering Instruments
• Effective Date: 10-May-2003
• Refers: ASTM E642-91(2002) - Standard Practice for Determining Application Rates and Distribution Patterns from Aerial Application Equipment
• Effective Date: 10-Oct-2002
• Refers: ASTM E642-91(1997)e1 - Standard Practice for Determining Application Rates and Distribution Patterns from Aerial Application Equipment
• Effective Date: 10-Apr-1997
• Refers: ASTM E1260-95 - Standard Test Method for Determining Liquid Drop Size Characteristics in a Spray Using Optical Nonimaging Light-Scattering Instruments
• Effective Date: 01-Jan-1995

Overview

ASTM F1738-23: Standard Test Method for Determination of Deposition of Aerially Applied Oil Spill Dispersants provides procedures for measuring how much of an aerially applied dispersant actually reaches the surface, using surrogates such as dyed water. As spray is released from aircraft or helicopters, a variety of factors - including wind and evaporation - can affect the actual deposition compared to the application dose. This standard allows for measurement and optimization of dispersant application equipment and verifies whether systems perform as specified, making it highly relevant to oil spill response professionals, equipment manufacturers, and researchers.

Key Topics

• Dispersant Deposition Measurement: Establishes methods for quantifying how much sprayed dispersant contacts the target area, measured in units like litres per hectare.
• Application Dosage vs. Deposition: Differentiates between the quantity of dispersant released (application rate) and what actually reaches the ground or water surface.
• Measurement Techniques:
  • Laser Measuring Instrumentation: Uses laser-based systems to gather data on droplet size and deposition patterns.
  • Coated Cards (e.g., Kromekote): Placed perpendicular to flight paths to collect spray, allowing manual or electronic analysis.
  • Glass Petri Dishes: Collects deposited surrogate for analysis with colorimetric methods.
  • Metal Troughs: Provides continuous sampling across a spray swath and supports efficient data capture over multiple runs.
  • String Method: Assesses spray pattern and width using dyed absorbent strings.
• Drop Size Characterization: Specifies the need to gather droplet size distribution data (e.g., volume median diameter, VMD) to evaluate atomization performance, crucial for dispersant effectiveness.
• Operational Considerations: Outlines the need for open, flat testing environments with minimal wind or turbulence to reduce drift and ensure representative measurements.
• Safety and Environmental Practices: Highlights the responsibility of users to address occupational health, safety, and environmental precautions based on specific dispersant formulations and regulatory requirements.

Applications

• Equipment Calibration and Validation: Used by manufacturers and oil spill responders to confirm that aerial dispersant application systems function as intended after modifications, repairs, or new deployments.
• Research and Development: Supports R&D for new dispersant application technologies by offering standardized measurement protocols.
• Performance Optimization: Data obtained can guide adjustments in settings or system components (such as boom or nozzle design) to improve deposition efficiency and minimize wastage from drift or evaporation.
• Technical Documentation: Results can be referenced in operational plans, regulatory submissions, and spill response training.

Related Standards

F1738-23 belongs to a suite of ASTM standards supporting oil spill response and aerial dispersant application:

• ASTM F1413/F1413M - Guide for design of oil spill dispersant application equipment.
• ASTM F1460/F1460M - Practice for calibrating dispersant application equipment.
• ASTM F1737/F1737M - Guide for use of dispersant application systems during response.
• ASTM E642 - Practice for determining application rates and distribution patterns from aerial application equipment.
• ASTM E1260 - Test method for determining liquid drop size characteristics.
• ASAE/ASABE S561.1 - Procedure for measuring drift deposits from sprayers.

For best practices in aerial dispersant operations, users are encouraged to consult all related standards to ensure comprehensive understanding and compliance.

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Keywords: oil spill dispersant, deposition measurement, aerial application, dispersant application systems, spray deposition, ASTM F1738, equipment calibration, drop size, oil spill response

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: F1738 − 23
Standard Test Method for
Determination of Deposition of Aerially Applied Oil Spill
Dispersants
This standard is issued under the fixed designation F1738; 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 ization established in the Decision on Principles for the
Development of International Standards, Guides and Recom-
1.1 This test method covers the measurement of the depo-
mendations issued by the World Trade Organization Technical
sition of an aerially applied dispersant surrogate, typically dyed
Barriers to Trade (TBT) Committee.
water, on the surface of the ground or water. The test method
of obtaining these measurements is described, and the analysis
2. Referenced Documents
of the results, in terms of dispersant use, is considered. There
2.1 ASTM Standards:
are a number of techniques that have been developed, and this
E642 Practice for Determining Application Rates and Dis-
test method outlines their application. These measurements can
tribution Patterns from Aerial Application Equipment
be used to confirm or verify the specifications of a given
E1260 Test Method for Determining Liquid Drop Size
equipment set, its proper functioning, and use.
Characteristics in a Spray Using Optical Nonimaging
1.2 This test method is applicable to systems used with
Light-Scattering Instruments
helicopters or airplanes.
F1413/F1413M Guide for Oil Spill Dispersant Application
1.3 This test method is one of four related to dispersant
Equipment: Boom and Nozzle Systems
application systems. Guide F1413/F1413M covers design,
F1460/F1460M Practice for Calibrating Oil Spill Dispersant
Practice F1460/F1460M covers calibration, Test Method
Application Equipment Boom and Nozzle Systems
F1738 covers deposition, and Guide F1737/F1737M covers the
F1737/F1737M Guide for Use of Oil Spill Dispersant Ap-
use of the systems. Familiarity with all four standards is
plication Equipment During Spill Response: Boom and
recommended.
Nozzle Systems
2.2 ASAE/ASABE Standard:
1.4 There are some exposure and occupational health con-
ASAE/ASABE S561.1 (R2013) Procedure for Measuring
cerns regarding the methods described. These are not discussed
Drift Deposits from Ground, Orchard, and Aerial Sprayers
in this test method since they are a function of dispersant
- Standard by The American Society of Agricultural and
formulation. Anyone undertaking such experiments should
Biological Engineers
consult the occupational health experts of the dispersant
manufacturer regarding the precautions to be used.
3. Significance and Use
1.5 Units—The values stated in SI units are to be regarded
3.1 The deposition of an aerially applied dispersant is
as standard. No other units of measurement are included in this
defined as the amount of an aerially applied dispersant that
standard.
contacts the surface; whereas, application dosage (frequently
1.6 This standard does not purport to address all of the
referred to as application rate) is the amount of material that is
safety concerns, if any, associated with its use. It is the
released per unit area by the delivery system. The units of
responsibility of the user of this standard to establish appro-
deposition are litres per hectare or U.S. gallons per acre. The
priate safety, health, and environmental practices and deter-
deposition may differ from the application dosage (volume of
mine the applicability of regulatory limitations prior to use.
material per unit area) for many reasons, such as, the effects of
1.7 This international standard was developed in accor-
wind on the spray and the evaporation of the dispersant after it
dance with internationally recognized principles on standard-
has been released from the aircraft.
1 2
This test method is under the jurisdiction of ASTM Committee F20 on For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Hazardous Substances and Oil Spill Response and is the direct responsibility of contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Subcommittee F20.13 on Treatment. Standards volume information, refer to the standard’s Document Summary page on
Current edition approved March 1, 2023. Published March 2023. Originally the ASTM website.
approved in 1996. Last previous edition approved in 2019 as F1738 – 19. DOI: Available from American Society of Agricultural and Biological Engineers
10.1520/F1738-23. (ASABE), 2950 Niles Road, St. Joseph, MI 49085, http://www.asabe.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F1738 − 23
3.2 This test method describes the measurement of the 5.1.1 Laser Measuring Instrumentation—The use of laser-
ability of a spray system to deposit a dispersant on oil. It is not based measuring techniques is becoming more common and
intended that this test method be used at the time of a spill.
can provide both drop size and deposition distribution. This
These techniques are intended to determine the equipment method employs laser scattering devices deployed in an array
performance during the development of new systems and after
on a flat surface (Test Method E1260), the number of these
the repair or significant modification of a system. devices depends on the specified horizontal range of these
devices and the amount of surface coverage desired by the test
3.3 The data obtained from the use of this test method can
group. The data are collected in the memory of the units and
be directly related to the deposition of dispersant on an oil
analyzed and processed upon completion of the test. With some
slick, and thus can serve to determine both the dispersant
units, it is possible to conduct multiple tests before recovery of
deposition and the drop size.
the data as the data are time-stamped.
3.4 Surrogate deposition and drop size data can be used as
5.1.2 Coated Cards—Standard cards specifically designed
a technical basis for the optimization of dispersant application
for the purpose (for example, Kromekote cards) of known area
equipment and its use.
are placed in a line perpendicular to the flight path, and
3.5 The choice of a dispersant surrogate may vary, typically extending over a distance 25 % greater than the expected swath
water is chosen along with a marker dye.
width. The cards typically have dimensions of 5 by 7 cm. There
should be about twenty cards placed across the flight path in
4. Apparatus and Materials order to have an adequate number of sampling points. In a
typical experimental setup, the distance between sampling
4.1 The basic concept is to provide a collection surface on
cards should be greater than one metre and less than three
which the aerially applied material is deposited. The amount of
metres. This criteria may require more or less than twenty cards
material and the deposition pattern and its drop size can be
depending on the spray system being tested. Each card should
measured using this surface. Several systems and methods
be identified by a unique label, indicating its place on the
have been developed, and each has its own advantages and
sampling line and the number of the spray pass. The marking
disadvantages.
should be made in such a fashion that it will not be removed by
4.2 These measurements require a large, flat open area (such
the dispersant surrogate, as well as Garrco Vision Pink dye
as a field or an airport) which is suitable for low-level flying
mixed at a ratio of 1:400 to provide color to the Kromekote
and maneuvering. The location should be away from human
cards. The cards are kept covered until just before the spray run
habitation or environmentally sensitive areas in order to
to reduce the possibility of contamination. The cards are placed
minimize problems due to noise and drifting spray.
in holders if wind can move these cards out of position. The
placement, uncovering, and retrieval of these cards is labor
4.3 These field programs should be conducted under low-
intensive. After the spray run, the cards are collected and
wind conditions in order to minimize drift. Near-surface
analyzed by machine (Practice E642, ASAE/ASABE S561.1
turbulence due to thermal gradients or atmospheric instability
(R2013)). The cards may be used to provide both drop size,
can contribute to a variation in the results. These measurements
spray width, and deposition pattern. This method may also be
cannot be carried out in the presence of precipitation or in
heavy concentrations of dust. used in combination with other methods to provide data.
5.1.3 Glass Petri Dishes or Similar Containers—Flat dishes
4.4 All tests are to be conducted with the flight path in an
of known area are placed in a line perpendicular to the flight
upwind direction. The upwind direction is chosen to simplify
path, and extending over a distance 25 % greater than the
the interpretation of the data and to conform with typical field
expected swath width. Dishes of a diameter of 120 to 140 mm
practice. It may be necessary to alter the flight path slightly for
are typically used. There should be about twenty dishes placed
changes in wind direction during the course of an experimental
across the flight path in order to have an adequate number of
program.
sampling points. In a typical experimental setup, the distance
4.5 It is common practice to use a surrogate, typically water,
between sampling dishes should be greater than one metre and
rather than the dispersant itself. Dye can be added to the water
less than three metres. These criteria may require more or less
to provide a measurement target. This dye should respond to
than twenty dishes depending on the spray system being tested.
the analytical method used in Section 5. A thickener should be
Each sampling dish should be identified by a unique label,
added to produce a viscosity similar to that of a dispersant.
indicating its place on the sampling line and the number of the
Special permission would be required to use a dispersant and
spray pass. The marking should be made in such a fashion that
permissions may also be required to apply a surrogate, and
it will not be removed by the dispersant surrogate, or rough
special precautions may be required to protect and clean the
handling. The sampling dishes are kept covered until just
area afterwards.
before the spray run to reduce the possibility of contamination.
The placement, uncovering, and retrieval of these dishes is
5. Deposition Measurement Methods
labor intensive. After the spray run, the dishes are collected and
washed with a suitable solvent, such as methanol or hexane, to
5.1 These techniques involve the use of a collecting surface
of known area and the measurement of the amount and collect the deposited material. The amount of dye present can
character of the dispersant deposited on this area. A variety of be determined by using a colorimeter sensitive to the dye used.
systems may be used, such as the following: The system must be calibrated using a sample of the dyed
F1738 − 23
surrogate and solvent mixture for that experimental pass. For diameter of a distribution
...

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: F1738 − 19 F1738 − 23
Standard Test Method for
Determination of Deposition of Aerially Applied Oil Spill
Dispersants
This standard is issued under the fixed designation F1738; 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 test method covers the measurement of the deposition of an aerially applied dispersant surrogate, typically dyed water,
on the surface of the ground or water. The test method of obtaining these measurements is described, and the analysis of the results,
in terms of dispersant use, is considered. There are a number of techniques that have been developed, and this test method outlines
their application. These measurements can be used to confirm or verify the specifications of a given equipment set, its proper
functioning, and use.
1.2 This test method is applicable to systems used with helicopters or airplanes.
1.3 This test method is one of four related to dispersant application systems. Guide F1413/F1413M covers design, Practice
F1460/F1460M covers calibration, Test Method F1738 covers deposition, and Guide F1737/F1737M covers the use of the systems.
Familiarity with all four standards is recommended.
1.4 There are some exposure and occupational health concerns regarding the methods described. These are not discussed in this
test method since they are a function of dispersant formulation. Anyone undertaking such experiments should consult the
occupational health experts of the dispersant manufacturer regarding the precautions to be used.
1.5 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this
standard.
1.6 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.
1.7 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:
E642 Practice for Determining Application Rates and Distribution Patterns from Aerial Application Equipment
This test method is under the jurisdiction of ASTM Committee F20 on Hazardous Substances and Oil Spill Response and is the direct responsibility of Subcommittee
F20.13 on Treatment.
Current edition approved Aug. 1, 2019March 1, 2023. Published August 2019March 2023. Originally approved in 1996. Last previous edition approved in 20152019 as
F1738F1738 – 19. –15. DOI: 10.1520/F1738-19.10.1520/F1738-23.
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
F1738 − 23
E1260 Test Method for Determining Liquid Drop Size Characteristics in a Spray Using Optical Nonimaging Light-Scattering
Instruments
F1413/F1413M Guide for Oil Spill Dispersant Application Equipment: Boom and Nozzle Systems
F1460/F1460M Practice for Calibrating Oil Spill Dispersant Application Equipment Boom and Nozzle Systems
F1737/F1737M Guide for Use of Oil Spill Dispersant Application Equipment During Spill Response: Boom and Nozzle Systems
2.2 ASAE/ASABE Standard:
ASAE/ASABE S561.1 (R2013) Procedure for Measuring Drift Deposits from Ground, Orchard, and Aerial Sprayers - Standard
by The American Society of Agricultural and Biological Engineers
3. Significance and Use
3.1 The deposition of an aerially applied dispersant is defined as the amount of an aerially applied dispersant that contacts the
surface; whereas, application dosage (frequently referred to as application rate) is the amount of material that is released per unit
area by the delivery system. The units of deposition are litres per hectare or U.S. gallons per acre. The deposition may differ from
the application dosage (volume of material per unit area) for many reasons, such as, the effects of wind on the spray and the
evaporation of the dispersant after it has been released from the aircraft.
3.2 This test method describes the measurement of the ability of a spray system to deposit a dispersant on oil. It is not intended
that this test method be used at the time of a spill. These techniques are intended to determine the equipment performance during
the development of new systems and after the repair or significant modification of a system.
3.3 The data obtained from the use of this test method can be directly related to the deposition of dispersant on an oil slick, and
thus can serve to determine both the dispersant deposition and the dropletdrop size.
3.4 Surrogate deposition and dropletdrop size data can be used as a technical basis for the optimization of dispersant application
equipment and its use.
3.5 The choice of a dispersant surrogate may vary, typically water is chosen along with a marker dye.
4. Apparatus and Materials
4.1 The basic concept is to provide a collection surface on which the aerially applied material is deposited. The amount of material
and the deposition pattern and its dropletdrop size can be measured using this surface. Several systems and methods have been
developed, and each has its own advantages and disadvantages.
4.2 These measurements require a large, flat open area (such as a field or an airport) which is suitable for low-level flying and
maneuvering. The location should be away from human habitation or environmentally sensitive areas in order to minimize
problems due to noise and drifting spray.
4.3 These field programs should be conducted under low-wind conditions in order to minimize drift. Near-surface turbulence due
to thermal gradients or atmospheric instability can contribute to a variation in the results. These measurements cannot be carried
out in the presence of precipitation or in heavy concentrations of dust.
4.4 All tests are to be conducted with the flight path in an upwind direction. The upwind direction is chosen to simplify the
interpretation of the data and to conform with typical field practice. It may be necessary to alter the flight path slightly for changes
in wind direction during the course of an experimental program.
4.5 It is common practice to use a surrogate, typically water, rather than the dispersant itself. Dye can be added to the water to
provide a measurement target. This dye should respond to the analytical method used in Section 5. A thickener should be added
to produce a viscosity similar to that of a dispersant. Special permission would be required to use a dispersant and permissions
may also be required to apply a surrogate, and special precautions may be required to protect and clean the area afterwards.
Available from American Society of Agricultural and Biological Engineers (ASABE), 2950 Niles Road, St. Joseph, MI 49085, http://www.asabe.org.
F1738 − 23
5. Deposition Measurement Methods
5.1 These techniques involve the use of a collecting surface of known area and the measurement of the amount and character of
the dispersant deposited on this area. A variety of systems may be used, such as the following:
5.1.1 Laser Measuring Instrumentation—The use of laser-based measuring techniques is becoming more common and can provide
both dropletdrop size and deposition distribution. This method employs laser scattering devices deployed in an array on a flat
surface (Test Method E1260), the number of these devices depends on the specified horizontal range of these devices and the
amount of surface coverage desired by the test group. The data are collected in the memory of the units and analyzed and processed
upon completion of the test. With some units, it is possible to conduct multiple tests before recovery of the data as the data are
time-stamped.
5.1.2 Coated Cards—Standard cards specifically designed for the purpose (for example, Kromekote cards) of known area are
placed in a line perpendicular to the flight path, and extending over a distance 25 % greater than the expected swath width. The
cards typically have dimensions of 5 by 7 cm. There should be about twenty cards placed across the flight path in order to have
an adequate number of sampling points. In a typical experimental setup, the distance between sampling cards should be greater
than one metre and less than three metres. This criteria may require more or less than twenty cards depending on the spray system
being tested. Each card should be identified by a unique label, indicating its place on the sampling line and the number of the spray
pass. The marking should be made in such a fashion that it will not be removed by the dispersant surrogate, as well as Garrco
Vision Pink dye mixed at a ratio of 1:400 to provide color to the Kromekote cards. The cards are kept covered until just before
the spray run to reduce the possibility of contamination. The cards are placeplaced in holders if wind can move these cards out
of position. The placement, uncovering, and retrieval of these cards is labor intensive. After the spray run, the cards are collected
and analyzed by machine (Practice E642, ASAE/ASABE S561.1 (R2013).(R2013)). The cards may be used to provide both
dropletdrop size, spray width, and deposition pattern. This method may also be used in combination with other methods to provide
data.
5.1.3 Glass Petri Dishes or Similar Containers—Flat dishes of known area are placed in a line perpendicular to the flight path,
and extending over a distance 25 % greater than the expected swath width. Dishes of a diameter of 120 to 140 mm are typically
used. There should be about twenty dishes placed across the flight path in order to have an adequate number of sampling points.
In a typical experimental setup, the distance between sampling dishes should be greater than one metre and less than three metres.
ThisThese criteria may require more or less than twenty dishes depending on the spray system being tested. Each sampling dish
should be identified by a unique label, indicating its place on the sampling line and the number of the spray pass. The marking
should be made in such a fashion that it will not be removed by the dispersant surrogate, or rough handling. The sampling dishes
are kept covered until just before the spray run to reduce the possibility of contamination. The placement, uncovering, and retrieval
of these dishes is labor intensive. After the spray run, the dishes are collected and washed with a suitable solvent, such as methanol
or hexane, to collect the deposited material. The amount of dye present can be determined by using a colorimeter sensitive to the
dye used. The system must be calibrated using a sample of the dyed surrogate and solvent mixture for that experimental pass. For
these measurements
...