ASTM D1709
Dart Drop Impact Test Standard

Plastic packaging films require durability under mechanical stress. One of the most widely accepted standards for evaluating such performance is ASTM D1709, which defines methods to determine the impact resistance of plastic films using a free-falling dart. This test provides valuable insight into a film’s toughness and helps manufacturers like Cell Instruments develop higher-quality materials for industries like packaging, food, pharmaceuticals, and medical devices.

Understanding the Dart Drop Impact Test and Its Importance

The dart drop impact test, governed by ASTM D1709, measures the energy required to cause failure in a plastic film by dropping a hemispherical dart from a defined height. This test simulates real-world conditions where films are subjected to mechanical stresses, such as dropping or stacking during transportation.

ASTM D1709 offers two test methods:

ASTM D1709

Test Method A:
Uses a 38.10 mm hemispherical dart dropped from 0.66 m. It’s suitable for films that fail between approximately 50 g and 6 kg.
Test Method B:
Involves a larger, 50.80 mm dart dropped from 1.52 m. It’s ideal for more impact-resistant films requiring dart weights from 0.3 kg to 6 kg.

Both methods are designed to find the 50% failure point, meaning the dart weight at which half of the specimens tested will fail.

Choosing Between Method A and Method B

Selecting the appropriate test method depends on the expected strength of the material. If you’re evaluating thin or moderately strong films, Method A is typically sufficient. For stronger, multi-layer, or specialty films, Method B provides a more demanding assessment.

Cell Instruments offers versatile solutions to handle both test methods with precision and efficiency.

Testing Procedures Based on ASTM D1709

ASTM D1709 outlines two main procedures for executing the dart drop impact test: the staircase method and the group method.

Staircase Method (Most Common):
- Begin with a dart weight near the estimated failure point.
- If a specimen fails, reduce the weight by a defined increment (ΔW).
- If it passes, increase the weight by ΔW.
- Continue testing until 10 failures and 10 non-failures have been recorded.
Group Method:
- Specimens are tested in groups of 10 using fixed dart weights.
- Weight is increased or decreased in uniform steps between groups.
- Less common but still acceptable when high throughput is required.

These methods are statistically robust and ensure high confidence in the final results.

Test Specimens and Equipment Setup

ASTM D1709 mandates that test specimens must be free of imperfections like pinholes or wrinkles, unless these are part of the testing variable. Proper sampling ensures reliable data.

Before the test:

Measure film thickness precisely.
Secure the specimen in a clamping ring without folds.
Align the dart head to ensure it drops vertically onto the specimen’s center.

FDT-01 Dart Drop Impact Tester from Cell Instruments meets all ASTM D1709 requirements, offering high-precision clamping and digital control for consistent and accurate results. The FDT-01 is widely trusted in quality control laboratories across the packaging and film industries.

Calculation of Impact Resistance

After testing, calculate the average impact failure weight using the number of failures at each dart weight. This value is essential for determining a material’s reliability during processing, transportation, and final use.

The calculation involves:

Recording all test results (fail/pass).
Using weighted averages to find the dart mass at which 50% of samples fail.

Why Choose Our Dart Impact Testing

ASTM D1709 Dart Drop Impact Test Standard

Cell Instruments provides industry-leading testing equipment like the FDT-01 Dart Drop Impact Tester, designed specifically for ASTM D1709 compliance. With customizable configurations, accurate data capture, and intuitive operation, our solutions help clients across the globe maintain consistent quality standards and reduce product failures.

Furthermore, we offer automation customization to streamline repetitive testing processes, significantly improving efficiency in high-volume production environments.

FAQs About ASTM D1709 and Dart Drop Impact Testing

1. What is ASTM D1709 used for?
ASTM D1709 determines the energy needed to cause failure in plastic film by dropping a dart from a set height, simulating real-world impact scenarios.

2. What’s the difference between Method A and Method B in ASTM D1709?
Method A uses a smaller dart and drop height, suitable for weaker films. Method B uses a larger dart and greater height, ideal for stronger films.

3. How is the dart weight selected for the test?
Start with an estimated failure weight. Adjust it up or down based on specimen performance in the staircase method until you achieve 10 passes and 10 failures.

4. Which instrument should I use for ASTM D1709 testing?
The FDT-01 Dart Drop Impact Tester from Cell Instruments is a reliable choice. It supports both Test Methods A and B with high accuracy.

5. Can dart impact results be compared across different test methods?
No. Results from Method A and Method B—or other impact standards—aren’t directly comparable due to differences in dart size, height, and energy measurement principles.