EPA’s Pesticide Drift Reduction Technologies Program -

A Voluntary Program – DRAFT Web page - May 2014

Verified drift reduction technologies can significantly reduce pesticide spray drift and loss 

from the application site, thereby keeping more pesticide on the crop and reducing risks

to nearby crops, the environment and people.

What is the Drift Reduction Technologies Program?

How to Test for Percent Drift Reduction

EPA-Verified Drift Reduction Technologies and the Star-Ratings

Adding Directions to Include DRTs on Pesticide Product Labels

Table of Verified DRT-Rated Technologies

Additional Resources

What is the Drift Reduction Technologies Program?

The EPA’s Drift Reduction Technologies (DRT) Program is a voluntary program that is intended to encourage the 

identification and use of DRTs that can substantially reduce drift of pesticide spray droplets from the target application 

site (e.g., a corn field) downwind to non-target areas. Examples of drift reduction technologies include spray nozzles, 

shrouds and shields, and nozzle/drift reducing adjuvant chemical combinations. Although these and other technologies 

have the potential to provide drift reduction, there is often uncertainty about their effectiveness or performance. 
Verification testing of technologies can provide a specific, quantitative measure of the effectiveness of the tested 

technology to reduce spray drift. The DRT Program focuses on technologies used for groundboom and aerial 

applications to field and row crops, which are the predominant pesticide use and application methods as well as the 

largest crop acreage in the United States. 

The EPA believes that over time, the DRT Program will move the agricultural sector away from unverified application 

technologies, toward the widespread use of low drift technologies. A robust adoption of this voluntary testing program 

by equipment and pesticide manufacturers and the resultant widespread use of DRTs by pesticide applicators will 

provide many benefits including:

 A standardized scientific approach to verifying and rating DRTs

 Reduced loss of pesticide product to drift and increased deposition of product on the intended crop, potentially 

improving efficacy of the pest or weed control

 Pesticide labels containing use directions with reductions for necessary spray restrictions, giving applicators 

more flexibility

 Reduced potential for off-target adverse effects, improved protection to sensitive crops and environments and 

nearby people 

How to Test for Percent Drift Reduction

EPA’s Offices of Research and Development and Pesticide Programs, with technical input from external experts, have 

developed a protocol Generic Verification Protocol for Testing Pesticide Application Spray Drift Reduction Technologies 

for Row and Field Crops. [insert link] for testing pesticide application technologies to estimate the percent reduction of 

spray drift.

This protocol addresses three testing approaches: low speed wind tunnels (to simulate application by groundboom

equipment), high speed wind tunnels (to simulate application by aircraft), and field testing (groundboom or aerial 

application). Generally, testing of smaller technologies, such as spray nozzles or nozzle/adjuvant combinations, would 

be conducted in wind tunnels which measure the amount of the relatively smallest driftable droplets (fines). The DRT 

rating of the technology will be based on the difference between the amounts of driftable fines from the technology 

being tested as compared to the reference nozzle. Use of a standardized DRT test protocol will enable EPA to make valid 

comparisons of test results. The drift reduction estimated by the study results would then be used to assign the 

technology its DRT rating.

EPA believes that field studies will most likely be used to determine drift reduction for shrouds or other large equipment 

that cannot fit into a wind tunnel. Field studies generate a deposition pattern and quantity of spray drift at downwind 

distances. EPA can use these data to estimate the percent drift reduction. Each field study is likely to be unique, and 

involve case-by-case considerations. 

EPA can use data from wind tunnel and field tests in the models for its risk assessments. EPA will “credit” the DRT-rated 

technology in the risk assessment-management decision rather than assuming no spray drift reduction. Pesticide labels 

that include use directions that specify DRT-rated technologies would also specify spray drift risk management 

measures, such as buffer zones, maximum wind speed, or release height. Since pesticide product labels will only specify, 

for example, to use a nozzle with a, for example, a DRT** rating, the label will not include brand names. Thus, 

applicators will have a variety of technologies from which to choose.

EPA notes that the protocol is limited to technologies for application to row and field crops because a large majority of 

agricultural pesticides are applied to these crops by groundboom and aerial equipment. A focus on encouraging the use 

of DRTs for these uses should have an overall greater benefit to drift reduction. In the future, EPA may consider 

expanding this voluntary program to application technologies for orchard and vineyard crops which require the use of 

significantly different application equipment.
Test Facilities

Technology manufacturers should contract with a qualified testing facility capable of performing this test with the 

appropriate equipment, methods and quality control standards. Refer to the protocol, section A8. Special Training and 

Certifications, for further information.

Submitting Test Reports to the EPA for Review and Evaluation

The EPA’s Office of Pesticide Programs has developed a format for data submission. [link] Send test reports to the EPA 

DRT box at drt.box@epa.gov. OPP will review the reports to verify the quality of the study and verify the tested 

technology’s drift reduction potential. Based on the data and information in the submitted report, OPP will verify 

whether the test was performed in an appropriate manner and only then determine if the data support a DRT rating. 

EPA-Verified Drift Reduction Technologies and the Star-Ratings

The EPA will offer four DRT ratings represented by one, two, three, or four stars for verified technologies which 

demonstrate at least 25% reduction in potential spray drift:

Adding Directions to Include DRTs on Pesticide Product Labels

The EPA encourages pesticide registrants to submit registration applications for new or amended registrations to include 

the use of verified DRTs on their product labels. As previously explained, the label will not include brand names, but will 

have use directions, such as, “Apply this product with DRT** technology.” Applications to include DRT label claims 

should be submitted according to standard requirements and procedures for applications for registration.

OPP will review registration applications and will credit the DRT label claim in its risk assessment and management 

decisions. Use of DRT-rated technologies can potentially result in significantly less off-target deposition, and could 

therefore mean that labels could contain use directions with reduced application restrictions, such as reduction or 

elimination of a buffer zone, or allowing applications during greater wind velocity or spray release height. Conversely, 

for identical or substantially similar pesticides without a DRT claim, EPA/OPP would not apply the credit of a DRT claim 

and therefore would likely require greater application restrictions to address potentially greater off-target drift and risks. 

DRT-Assigned Ratings

25% to 49%

50% to 74%

75% to 89%

90% +
Pesticide applicants and registrants can choose to label their products for use with both standard application equipment 

(non-DRT) and DRT-rated equipment or technologies, thus giving the applicator a choice. In this case such labels would 

have two sets of application restrictions: One set of restrictions if the product is applied without DRT and another set of 

restrictions if the product is applied with a DRT.

Table of Verified DRT-Rated Technologies

Pesticide applicators who choose to use a product labeled with a specific DRT claim can locate the application 

technologies that have been verified for that DRT claim using the Table of Verified DRT-Rated Technologies. For 

example, if a label allows the applicator to use DRT*** technology, the applicator would refer to the EPA’s DRT website 

to see the identities of the specific DRT*** rated technologies to make the application. 

Table of Verified DRT-Rated Technologies for Groundboom Applications

Manufacturer DRT-Rated Technology System Pressure (psi)

DRT* Technologies

DRT** Technologies

DRT*** Technologies

DRT**** Technologies

Table for Verified DRT-Rated Technologies for Aerial Applications

Manufacturer DRT-Rated Technology System Pressure (psi)

DRT* Technologies
DRT** Technologies

DRT*** Technologies

DRT**** Technologies

Additional Resources

 Federal Register notice: EPA DRT Program [need link to FR notice]