OTR (Oxygen Transmission Rate) testers play a crucial role in various industries, especially in packaging, food, and pharmaceutical sectors. These testers help determine how much oxygen can pass through a material over a specific period, which is vital for ensuring product quality and shelf - life. As an OTR tester supplier, I've witnessed numerous common mistakes made by OTR testers. Understanding these mistakes can help users achieve more accurate results and make the most of their testing equipment.
1. Improper Sample Preparation
One of the most prevalent mistakes is improper sample preparation. The sample used for OTR testing must be representative of the material being evaluated. Cutting the sample with dull blades can cause damage to the edges, leading to inaccurate results. For example, if the sample has rough or torn edges, oxygen may leak through these damaged areas, artificially increasing the measured oxygen transmission rate.
Moreover, ensuring the sample is clean is essential. Dust, fingerprints, or other contaminants on the sample surface can interfere with the oxygen transmission process. A dirty sample might create barriers or channels that affect the normal flow of oxygen, thus distorting the test results. To avoid these issues, it is recommended to use sharp cutting tools and clean the sample surface with appropriate solvents before testing.
2. Incorrect Testing Conditions
Maintaining the right testing conditions is critical for accurate OTR measurement. Temperature and humidity can significantly impact the oxygen transmission rate. Most OTR testers are designed to operate within a specific temperature and humidity range. If the testing environment deviates from these recommended conditions, the results can be unreliable.
For instance, an increase in temperature generally leads to an increase in the oxygen transmission rate because higher temperatures provide more energy for oxygen molecules to move through the material. Similarly, humidity can affect the material's structure and the solubility of oxygen in the material. Some materials may absorb moisture, which can either increase or decrease their oxygen permeability depending on the nature of the material.
It is essential to use environmental control systems to maintain stable temperature and humidity levels during testing. Our Lab - Grade OTR Analyzer is equipped with advanced environmental control features to ensure accurate testing under various conditions.
3. Inadequate Calibration
Calibration is a fundamental step in ensuring the accuracy of OTR testers. Over time, the sensors and other components of the tester may drift, leading to inaccurate readings. Many users neglect regular calibration, assuming that the tester will continue to provide accurate results indefinitely.
Inadequate calibration can result in significant errors in the measured oxygen transmission rate. For example, if the oxygen sensor is not calibrated correctly, it may over - or under - estimate the amount of oxygen passing through the sample. This can have serious consequences, especially in industries where precise oxygen transmission data is crucial for product quality control.
We recommend calibrating the OTR tester at regular intervals, following the manufacturer's guidelines. Our Oxygen Transmission Tester comes with a detailed calibration procedure to help users maintain the accuracy of their equipment.
4. Ignoring the Influence of Gas Purity
The purity of the gases used in OTR testing can also affect the results. Oxygen and carrier gases with impurities can introduce additional oxygen or other substances that interfere with the measurement. For example, if the carrier gas contains traces of oxygen, it can artificially increase the measured oxygen transmission rate.
It is important to use high - purity gases for OTR testing. The gas cylinders should be properly maintained and regularly checked for purity. Using low - quality or impure gases can not only lead to inaccurate results but also damage the tester's sensors over time.
5. Lack of Operator Training
OTR testers are sophisticated instruments that require proper training to operate effectively. Many operators may not be fully aware of the tester's features, functions, and limitations. This lack of training can lead to mistakes during sample loading, test setup, and data interpretation.
For example, an inexperienced operator may not know how to properly load the sample into the tester, which can cause leaks or misalignment. They may also misinterpret the test results, leading to incorrect decisions regarding product quality.
We offer comprehensive training programs for users of our Oxygen Transmission Rate Analyzer. These programs cover everything from basic operation to advanced troubleshooting, ensuring that operators can use the tester to its full potential.
6. Overlooking Data Analysis
Collecting accurate data is only half the battle; analyzing the data correctly is equally important. Many users focus solely on obtaining the oxygen transmission rate value without considering other factors such as the repeatability of the results, the confidence interval, and the statistical significance.
For example, if the test results show a high degree of variability, it may indicate a problem with the testing procedure or the sample itself. Ignoring these issues can lead to false conclusions about the material's oxygen barrier properties.
Proper data analysis involves using statistical methods to evaluate the reliability of the results. This can help identify trends, outliers, and potential sources of error. Our OTR testers come with software that provides advanced data analysis tools to assist users in making informed decisions.
7. Not Considering the Material's Anisotropy
Some materials, such as films and laminates, may exhibit anisotropic behavior, meaning their oxygen transmission rate can vary depending on the direction of measurement. Ignoring this anisotropy can lead to inaccurate results.
For example, a film may have a different oxygen transmission rate in the machine direction compared to the transverse direction. If the sample is not tested in multiple directions, the reported oxygen transmission rate may not be representative of the material's overall performance.
When testing anisotropic materials, it is important to take samples from different directions and perform multiple tests to obtain a more comprehensive understanding of the material's oxygen barrier properties.
8. Failure to Follow Standard Test Methods
There are several international standards for OTR testing, such as ASTM D3985 and ISO 15105 - 1. These standards provide detailed procedures for sample preparation, testing conditions, and data reporting. Failure to follow these standard test methods can lead to inconsistent and unreliable results.
Using non - standard test methods may also make it difficult to compare the results with other studies or industry benchmarks. It is important to ensure that all OTR tests are conducted in accordance with the relevant standards.
Conclusion
In conclusion, avoiding these common mistakes is essential for obtaining accurate and reliable OTR test results. As an OTR tester supplier, we are committed to providing high - quality testing equipment and comprehensive support to our customers. Our Lab - Grade OTR Analyzer, Oxygen Transmission Tester, and Oxygen Transmission Rate Analyzer are designed to meet the highest standards of accuracy and reliability.
If you are interested in improving your OTR testing process or purchasing our OTR testers, we encourage you to contact us for a detailed discussion. Our team of experts is ready to assist you in finding the best solution for your specific needs.
References
- ASTM D3985 - Standard Test Method for Oxygen Gas Transmission Rate Through Plastic Film and Sheeting Using a Coulometric Sensor.
- ISO 15105 - 1 - Plastics -- Film and sheeting -- Determination of gas - transmission rate -- Part 1: Differential - pressure method.
- Various technical papers on oxygen transmission testing in peer - reviewed scientific journals.
