This standard specifies the conditions, equipment, procedures and test reports for temperature and humidity conditioning of transport packages. This standard applies to temperature and humidity conditioning of transport packages during basic tests. GB/T 4857.2-1992 Packaging Humidity conditioning of transport packages GB/T4857.2-1992 Standard download decompression password: www.bzxz.net
This standard specifies the conditions, equipment, procedures and test reports for temperature and humidity conditioning of transport packages. This standard applies to temperature and humidity conditioning of transport packages during basic tests.

National Standard of the People's Republic of China
Packaging Transport packages-Temperature and humidity conditioning
Packaging Transport packages-Temperature and humidity conditioning GB/T 4857.2-92
ISO 2233-1986
Replaces GB4857.2-84
This standard is equivalent to the international standard ISO2233-1986 "Packaging-Complete and fully filled transport packages-Temperature and humidity conditioning during testing".
1 Subject content and scope of application
This standard specifies the conditions, equipment, procedures and test reports for temperature and humidity conditioning of transport packages. This standard is applicable to temperature and humidity conditioning of transport packages during basic tests. 2 Principle
Place the test sample in a temperature and humidity conditioning box (chamber) and experience a predetermined time under the predetermined temperature and humidity conditions. 3 Temperature and humidity conditioning treatment conditions
Based on the characteristics of the transport package and the environmental conditions that may be encountered during the circulation process, select one of the temperature and humidity conditions in Article 3.1 and one of the conditioning treatment times in Article 3.2 to carry out temperature and humidity conditioning treatment. 3.1 Temperature and humidity conditions
3.1.1 Temperature and humidity conditions, see the table below:
3.1.2 Allowable error
Temperature, ℃
Relative humidity, %
Free relative humidity
3.1.2.1 Temperature error
For conditions 1, 2 and 11, the temperature error is ±3℃*Condition 4, the error is ±1℃; for other conditions, the error is ±2℃ Approved by the State Administration of Technical Supervision on November 25, 1992 252
Implementation on June 1, 1993
GB/T 4857.2—92
Note: ① When using condition 4, it must be ensured that no condensation occurs. ② The temperature errors listed may not be those necessary to maintain the required relative humidity. Therefore, in order to achieve the required relative humidity error, the temperature error requirements may need to be more stringent. 3.1.2.2 Relative humidity error
If the relative humidity has been pre-specified (see table above), the average relative humidity in any 1 hour during the temperature and humidity conditioning process shall not exceed 5% of the specified relative humidity; continuous fluctuations in relative humidity are possible, but shall not exceed ±5% of the specified value: occasional excursions are allowed, but the frequency, amplitude and duration of occurrence shall not have an adverse effect on the conditioning of the transport package. Note: ① The average relative humidity should be obtained from the average of at least 10 measurements over a period of more than 1 hour, or obtained through continuous recording of the instrument. ② The proposed ±5% relative humidity error represents the total variation that can be expected in a well-designed temperature and humidity conditioning chamber (room). Most transport packages respond more slowly to changes in atmospheric humidity than fluctuations in relative humidity in the temperature and humidity conditioning chamber (room). If the average relative humidity in the working space measured in any 1 hour during the test is within ±5% of the specified relative humidity, then even large fluctuations will not have a significant impact on the moisture content of the transport package. For the meaning of the terms "average relative humidity", "relative humidity fluctuation" and "adjustment deviation", please see Appendix A (reference). 3.2 Temperature and humidity conditioning treatment time
4, 8, 16, 24, 48, 72 hs or 7.14.21, 28 d. 4 Instruments and equipment
4.1 Temperature and humidity chamber (room)
For each temperature and humidity chamber (room), the scope of the working space should be specified. The working space should be able to maintain the specified conditioning conditions, and its temperature and humidity can be continuously recorded and maintained within the allowable error specified in Article 3.1.2. 4.2 Drying oven (room)
Reduce the moisture content of certain test samples to below the moisture content required for temperature and humidity conditioning treatment. 4.3 Recording Instruments
The recording instrument shall have sufficient sensitivity and stability, and the measurement accuracy of temperature shall be accurate to 0.1°C and the relative humidity shall be accurate to 1%. It shall also be able to make continuous records. If the interval between each test record is not more than 5 minutes, the record is also considered to be continuous. While meeting the above measurement accuracy requirements, the recording instrument shall have sufficient response speed to accurately record the temperature change of 4°C per minute and the relative humidity change of 5% per minute.
5 Procedures
Place the prepared test sample in the working space of the temperature and humidity chamber (room), and place the test sample overhead so that its top surface, surroundings and at least 75% of the bottom area can freely contact the temperature and humidity conditioned air. Condition the test sample according to the predetermined temperature conditioning conditions and time. The treatment time starts from 1 hour after the specified conditions are reached.
No condensation water is allowed to drip onto the test sample during the conditioning process. If the test sample is made of a material with hysteresis, such as fiberboard, it may be necessary to dry it before the temperature and humidity conditioning treatment. The method is: place the test sample in a drying oven and dry it for at least 24 hours, so that when it is transferred to the specified conditions, the test sample can reach a near equilibrium by absorbing moisture. When the specified relative humidity is not greater than 40%, no drying treatment is performed. 6 Test Report
Various test reports on transport packages that have been treated with temperature and humidity, such as stacking tests, vertical impact drop tests, horizontal impact tests, vibration tests, etc., must include the following: 1. The temperature, relative humidity and time during the temperature and humidity conditioning treatment; b. The temperature and relative humidity of the test site during the test. 253
GB/T 4857.2—92
Appendix A
Notes on the determination of relative humidity
(reference)
The continuous record of relative humidity will show periodic changes. Therefore, an accurate value that can describe the size and change of this feature in detail is required.
Refer to the following typical record:
A1 Average relative humidity
When the highest value Umx and the average value of U degrees appear continuously in a 1hn cycle (0), it is obtained by formula (A1) and (A2): 0
Unn and the lowest value UminUinz,
Umin, the relative humidity
(Uml +U +* +U + Umin +U.in2 +.. +Uainn).(Al)2n
Relative humidity fluctuation
UU +U
·(A2)
The fluctuation range of relative humidity can be obtained by the upper and lower limits between ① and the average maximum relative humidity port and the average minimum relative humidity U. Www.bzxZ.net
Here: ma
Occasional deviation
GB/T 4857.2-92
The occasional deviation of relative humidity is expressed by U and Umin. Additional remarks:
This standard was proposed by the Ministry of Machinery and Electronics Industry of the People's Republic of China. This standard was drafted by the Electronic Standardization Institute of the Ministry of Machinery and Electronics Industry. The main drafters of this standard are Fang Lina and Xu Yunchi. (A4)
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