Front page / How do I plan packaging and drop testing for a moulded product (ISTA 3A)?
How do I plan packaging and drop testing for a moulded product (ISTA 3A)?
If your product ships as individual parcels, the usual reference test is ISTA 3A, which ISTA describes as a general simulation test for individually packaged products of up to 70 kg (150 lb) shipped through parcel delivery systems. It combines conditioning, a series of drops, random vibration and, for some package shapes, extra impact tests. Earlier in design, cheaper ISTA 1-series or 2-series screening tests help compare packaging ideas before you commit.
Which ISTA series does what
| Series | ISTA's description | Typical use |
|---|---|---|
| 1-Series | non-simulation integrity tests; screening, not meant to simulate the environment | early design, quick benchmark |
| 2-Series | more thorough screening for refining designs; not predictive of shipping performance | comparing packaging options |
| 3-Series | simulation of the damage-producing motions, forces and sequences of transport | pre-launch check, e.g. 3A for parcels |
| 4-Series | customised plans tied to a user-defined distribution pattern | known, specific supply chains |
| 6-Series | created by an ISTA member to reflect their own distribution conditions | retailer or carrier requirements |
| 7-Series | comparing two or more transport container designs | container development |
ISTA 3A in outline
ISTA's public overview of 3A (2018 version) defines four package types. Small packages are under 13,000 cm³ (800 in³), no longer than 350 mm (14 in) and no heavier than 4.5 kg (10 lb). Flat packages have a shortest side of 200 mm (8 in) or less, a next side at least four times longer, and a volume of 13,000 cm³ or more. Elongated packages are at least 900 mm (36 in) long, with each other side 20 percent or less of the length. Standard packages are everything else; if a package is both flat and elongated, it is tested as elongated.
For standard, flat and elongated packages, the overview's sequence is:
- Atmospheric preconditioning at ambient conditions, with optional conditioning at chosen temperature and humidity.
- A first set of 9 drops, with height depending on package weight.
- Random vibration, with optional vibration under low pressure to simulate air transport.
- A second set of 8 drops, including a drop onto a hazard.
- Extra tests for flat and elongated packages: rotational edge drop from 200 mm (8 in), and concentrated or bridge impact using a hazard box dropped from 400 mm (16 in).
Small packages follow a similar sequence of drops and vibration, partly inside a bag. ISTA requires one sample but encourages five or more runs with new samples to improve confidence. It also notes that 3A tests package and product together and may not cover every condition, such as moisture or unusual handling. Full drop heights and limits are in the procedure itself, which ISTA sells.
A practical plan for a new product
- Write pass criteria first. The 3A overview says the shipper must decide before testing what counts as product damage, what damage is tolerable and what package condition is acceptable, for example no cracks, no loose parts and the product still works.
- Screen early. Run quick drops on printed or early parts to find weak features such as thin bosses, snap hooks and corners.
- Test with production parts. Use moulded parts in the production resin and colour, as material and moulding affect toughness.
- Include cold. If the product ships in winter, ask for conditioning at low temperature, since many plastics become less impact resistant when cold.
- Plan the lab. The 3A overview marks which steps are required for ISTA certification and refers to sending samples to an ISTA Certified Laboratory, so decide early whether you need a certified result.
Summary based on ISTA's public overview and test procedure pages. The purchased procedure governs actual testing.
Questions buyers ask
Is ISTA 3A mandatory?
It is a voluntary industry procedure. Some retailers, marketplaces or customers require specific ISTA tests, so check their packaging requirements.
Does passing 3A mean no damage in transit?
No. ISTA points out that 3A test levels come from general data, so they may not match any particular distribution system.
Which test for pallet shipments?
3A covers individual parcels. ISTA has other procedures for different shipment types; its selection guidelines help choose.
Can packaging fix a fragile part?
Partly. If drops crack the same feature every time, a design change to the part, such as a larger radius or thicker rib, may be cheaper than more packaging.
Sources
- International Safe Transit Association, Test procedures
- International Safe Transit Association, ISTA 3A overview (PDF)