CIPAC MT 184, published by the Collaborative International Pesticides Analytical Council (CIPAC), and formulations that form a suspension when diluted with water (e.g., wettable powder – WP, water-dispersible granules – WG, suspension concentrate – SC, water-soluble granules – SG, oil suspension – OD, etc.) to determine suspensibility. CIPAC is an international organization that standardizes analytical methods and physicochemical test procedures for plant protection products; CIPAC methods are widely recognized in plant protection product registration dossiers, product specifications, and quality control processes.
Note on regulatory status: CIPAC MT 184 is a general method that replaces formulation-specific historical methods (e.g., MT 15 for WP, MT 75 for WG, MT 161 for SC) and is widely used in current regulatory practice. The method is applicable to all formulations that form a suspension after dilution and allows for a standardized evaluation regardless of the formulation type.
The basic principle of the test is as follows:
- The formulation is prepared in water of standard hardness at the concentration specified in the product specification.
- The suspension is thoroughly mixed and allowed to stand in a standard measuring cup or graduated cylinder for a specified period of time (usually 30 minutes).
- Once the waiting period has elapsed, a sample is taken from the upper portion (usually the top 9/10 or a specified volume).
- The amount of active ingredient contained in the upper suspension is calculated relative to the original total amount of active ingredient to determine the percentage of suspensibility (% Suspensibility).
- The active ingredient is determined using an analytical method specific to the formulation (HPLC, GC, etc.).
- If necessary, suspension stability after wetting and sedimentation behavior can also be evaluated.
The basic parameters reported in the study are as follows:
- Suspension capacity (%)
- Test concentration and volume of the prepared suspension
- Water hardness ( usually standard hardness, e.g., 342 ppm CaCO₃) and temperature
- Residence time ( usually 30 minutes) and sampling depth
- Dispersion method used (stirring speed, duration, number of cycles)
- Method for Determining the Active Ingredient and Analytical Results
- Observations on Sedimentation and Flocculation
- Comparison with the specification value (if available)
- Data on Measurement Uncertainty and Repeatability
Why is this being done?
CIPAC MT 184 is conducted for the following scientific, technical, and regulatory purposes:
- Evaluation of Product Performance: Determination of the formulation's ability to form a homogeneous suspension after dilution with water and to remain in suspension
- Ensuring Application Quality: Providing essential data to ensure that the active ingredient is distributed uniformly throughout the tank during the spraying process and does not precipitate
- Verification of compliance with the product specification: Determining whether the suspension capacity meets the specified value (e.g., minimum suspension capacity in %)
- Quality Control: Monitoring consistency across production batches and ensuring product quality
- Formulation Development: Optimization of the selection of dispersants, wetting agents, thickeners, and excipients
- Assessment of Storage Stability: Monitoring whether the ability to remain in suspension is maintained after aging
- Formulation-Type-Independent Comparison: Comparison of Different Formulation Types (WP, WG, SC, etc.) Using a Standard Method
- Support for registration documentation: Use in pesticide registration documentation (e.g., EU Regulation 1107/2009, national regulations) and product specifications
- Evidence-Based Approach: Contribution to a comprehensive evaluation of the product in conjunction with other physicochemical tests (wetting time, spreading time, sieve test, suspension stability, foaming, viscosity), analytical data, and stability studies
CIPAC MT 184 does not, on its own, provide comprehensive information about product quality or biological efficacy. It allows for a physicochemical performance evaluation; the results must be interpreted in conjunction with other formulation tests, analytical data, stability studies, and the requirements of the specifications.
As part of our nano-testing services, we conduct the suspension tests specified in CIPAC MT 184 with scientific rigor within our accredited laboratory infrastructure and under our quality management system. Our scope of services includes the following:
Method Selection and Validation
- Assessment of the Applicability of CIPAC MT 184 Based on Formulation Type and Regulatory Requirements
- Selection, calibration, and validation of the formulation-specific method for determining active ingredients (HPLC, GC, etc.)
- Method Validation: Linearity, Accuracy, Repeatability, and Reproducibility
- Evaluation and Reporting of Measurement Uncertainty
- Documentation of method-specific limitations and conditions of use
For information on method selection, analytical strategy, sample acceptance criteria, specification comparison, the testing schedule, and reporting procedures for your suspension capacity tests under CIPAC MT 184, please feel free to contact Nano-Test.