What’s the differences between ISTA 3E and ISTA 3H?
Test Procedure 3H is a general simulation test for mechanically handled bulk loads.
It is intended for bulk loads of the same product but it can also be considered for mixed loads.
It can be used to evaluate the protective performance of bulk transport systems related to vibrations, shocks and other stresses normally encountered during handling and transportation.
It can be used to evaluate interior dunnage.
The test levels are based on general data and may not represent any specific distribution system.
The package and product are considered together and not separately.
Some conditions of transit, such as moisture, pressure or unusual handling, may not be covered.
Test Procedure 3H covers testing of bulk loads made up of one transport container or system consisting of the same product that because of their size and/or weight must be handled by mechanical means, for example, automotive parts in reusable racks.
The shipper shall determine the following prior to testing:
what constitutes damage to the product and
what damage tolerance level is allowable, if any, and
the correct methodology to determine product condition at the conclusion of the test and
the acceptable package condition at the conclusion of the test.
We can see clearly the different requirements between ISTA 3E and 3H from following chart:
Test Category | Test Type | ISTA 3H | ISTA 3E | Note |
Atmospheric Preconditioning | Temperature and Humidity | Ambient | Required |
Atmospheric Conditioning | Controlled Temperature and Humidity | Temperature and Humidity chosen from chart | Optional |
Shock | Horizontal Impact | 4 and 6 mph (1.8 and 2.7 m/s)300 ms Trapezoidal | / | Required for Rail Shipments Only |
2 mph (0.9 m/s)15ms half sine | 1.2m/s | Required |
Inclined Impact (for ISTA 3E, select either horizontal or inclined shock) | 1.2m/s | / |
Rotational Flat Drop | 4 in (100 mm) | 8 in (200 mm) | Required |
Rotational Edge Drop | 4 in (100 mm) | 8 in (200 mm) | Required |
Vibration | Random | Overall Grms level varies with Mode of Transport, max. 82.58 mm P-P displacement | 0.54Grms, 45.13mm P-P displacement | Required |
Compression (Alternative methods allowed - select one test type) | Machine Apply and Release | Calculated Test Force x1.4 | Optional | Required |
Machine Apply and Hold | Calculated Test Force x |
Weight and load Spreader | Calculated Test Force x |
Steel Spring Truck Random Vibration is same with ISTA 3E, additionally, there are another two types vibration test:
1. For Air-Ride Truck Random Vibration:
The following breakpoints shall be programmed into the vibration controller to produce the acceleration versus frequency profile(spectrum) below with an overall Grms level of 0.28. The theoretical stroke required to run this vibration profile is 82.58 mm (3.251in) peak to peak.
2. For Railcar Random Vibration:
The following breakpoints shall be programmed into the vibration controller to produce the acceleration versus frequency profile(spectrum) below with an overall Grms level of 0.13. The theoretical stroke required to run this vibration profile is 21.26 mm (0.837in) peak to peak.
Calculate the test time
Estimate the transportation distance of the package during land transportation, and then use the following formula to determine the test time:
Test time (minutes) = transportation distance (miles) ÷ 5. The longest test time is 240 minutes
or
Test time (minutes)=transportation distance (km) |÷8. The longest test time is 240 minutes
For example:
If the estimated transportation distance is 750 miles, the test time is 150 minutes. If the estimated transportation distance is 1000 kilometers, the test time is 125 minutes.
Choose suitable product to do random vibration test
If customer wants to do test under both ISTA 3E and 3H procedures, then CME KRD70 series hydraulic vibration shakeris the best choice, which can cover all test specifications above, especially for large displacement 82.58 mm; while the normal electronic-dynamic shaker is difficult to meet long stroke and low frequency test, hydraulic shaker is the proper one to do these tests.
KRD70 series hydraulic vibration shaker
Besides, CME Technology provides other test equipment, as KRD12 Horizontal shock Test System, KRD100 inclined Impact tester, KRD40 Drop Tester, KRD101 Compression Tester......All these mechanical testing systems is capable of doing above ISTA certification.
Have any enquiry? Please contact our sales: info@creditcme.com .
