Appendix B – Supplementary Thermal Performance Assessment
This appendix documents a supplementary thermal performance assessment performed using TOP64 and TOP55 eutectic cooling plates with nominal eutectic values of -21°C and -26°C.
From left to right: TOP64 (-21°C), TOP55 (-21°C) and TOP55 (-26°C) eutectic plates positioned within the ATP-IN classified EPP insulated container.
The cooling media were introduced at different stages of the assessment to observe the influence of cooling capacity, nominal eutectic value and available thermal reserve on product temperature development.
Chapters in Appendix B
B.1 Introduction
This supplementary assessment was performed to further investigate the relationship between eutectic cooling media, available cooling capacity, product thermal mass and achievable product temperatures under elevated ambient conditions.
The evaluation utilised a series of Olivo TOP64 and TOP55 eutectic plates conditioned to nominal eutectic values of -21°C and -26°C. The objective was not to validate or reject a specific cooling medium, insulated container or distribution system, but to observe the practical thermal behaviour of the combined cooling system under controlled conditions.
Prior to commencement of the assessment, the ATP-IN classified EPP insulated box was pre-conditioned using a fully frozen TOP64 eutectic plate with a nominal eutectic value of -21°C. After completion of the pre-conditioning phase, the final test configuration was assembled and the practical assessment commenced.
Throughout the assessment, different cooling media were introduced sequentially in order to observe the influence of additional cooling capacity on the temperature development of the simulated product load.
The observations documented in this appendix should therefore be interpreted as a practical thermal assessment of the test configuration described herein and should not be regarded as a validation of any insulated container, packaging system, cooling medium or distribution process.
B.2 Test Objectives
The objectives of the supplementary assessment were to:
- Observe the thermal behaviour of TOP64 and TOP55 eutectic cooling plates with nominal eutectic values of -21°C and -26°C.
- Monitor temperature development within the simulated product load and surrounding airspace.
- Evaluate the influence of sequential replacement of cooling media on observed temperatures.
- Compare observed temperatures with commonly referenced frozen-product temperature criteria of -18°C and -15°C.
- Obtain additional insight into the relationship between cooling capacity, thermal mass, ambient temperature and product temperature performance.
B.3 Assessment Timeline
The timeline below summarises the principal activities performed during the supplementary assessment. The corresponding graph, presented below the table, illustrates the various assessment phases and the observed temperature development.
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| Time | Activity |
|---|---|
| 10:45 Phase: 1 | Start of EPP box pre-conditioning using a fully frozen TOP64 (-21°C) eutectic plate |
| 11:45 | Completion of pre-conditioning phase |
| 12:35 Phase: 2 | Start of assessment using a newly conditioned TOP64 (-21°C) eutectic plate (100% frozen) |
| 13:33 Phase: 3 | Replacement of cooling medium with a second TOP64 (-21°C) eutectic plate (100% frozen) following temperature stabilisation |
| 14:36 Phase: 4 | Replacement of TOP64 plate by a fully frozen TOP55 (-21°C) eutectic plate |
| 16:40 Phase: 5 | Introduction of a TOP55 (-26°C) eutectic plate estimated to be approximately 75% frozen |
| End of assessment | Temperature monitoring completed and data analysed |
The graph illustrates the temperatures measured beneath the eutectic plates, within the simulated product load and under ambient conditions.
The shaded sections indicate the various assessment phases, including pre-conditioning of the EPP box, evaluation of fully frozen TOP64 (-21°C) eutectic plates, evaluation of a TOP55 (-21°C) eutectic plate and the final assessment phase using a TOP55 (-26°C) eutectic plate.
The dashed red reference line indicates the commonly referenced frozen-product transport temperature criterion of -15°C..
B.4 Test Observations
The assessment was conducted under ambient temperatures approaching 30°C throughout the monitoring period. The ambient logger recorded an average temperature of approximately 29.8°C. imageimage.png†image0 (Image: Logger statistics table)
During the assessment, sequential replacement of cooling media was performed in an effort to increase the available cooling capacity within the insulated test configuration.
The results demonstrated that changes in cooling medium capacity and nominal eutectic value influenced the observed temperature profile. However, the recorded temperatures also appeared to be affected by the interaction between:
- Available cooling capacity
- Product thermal mass
- Ambient temperature
- Heat ingress into the insulated container
- Test duration.
The temperature profile obtained during the assessment shows the response of both the frozen-product simulation and chilled-product simulation to the successive introduction of cooling media having different capacities and nominal eutectic values. The reference temperatures of -18°C, -15°C and -25°C are included for comparison purposes. imagechart (25).jpeg†image1 (Image: Temperature profile with reference lines)
At the conclusion of the assessment period, the TOP55 (-26°C) eutectic plate used during the final phase was estimated to be approximately 75% frozen when introduced into the test configuration. The observations obtained during this final stage should therefore be interpreted with this limitation in mind.
B.5 Scope and Limitations
This supplementary assessment was intended solely to document the thermal behaviour observed within the specific test configuration described in this appendix.
The observations should not be interpreted as:
- Validation of an ATP-IN insulated container
- Validation of an ATP-IR container
- Validation of a complete packaging system
- Validation of a transport operation
- Validation of a frozen-food distribution process.
The results should be considered practical observations obtained under the described conditions and may contribute to discussions concerning cooling-medium selection, thermal reserve, product thermal mass and the principle of “Fit for Intended Use” within temperature-controlled logistics applications.
B.6 Related Assessment Documentation
← Return to Main Assessment Report
← View Appendix A – Test Protocol and Measurement Setup
Written by Eppo Woortman
From Assumptions to Assurance in Logistics
Temperature & Fresh Preservation Consultant
This article is part of the developing FATA-IN-LOGISTICS knowledge initiative, dedicated to temperature control, freshness preservation and sensitive goods logistics.