TP 14850 Testing for Dangerous Goods Containers

TP 14850 is Transport Canada’s standard for small containers carrying dangerous goods in Classes 3, 4, 5, 6.1, 8 and 9. Small means up to 450 litres. Above that it is a different regime.

It is worth being clear about who this is for, because it is a different buyer from the rest of package testing. Distribution testing asks whether your product survives the trip to a customer. TP 14850 asks whether a container design is fit to carry dangerous goods at all. The people who need it are container manufacturers, importers and reconditioners: the makers of drums, jerricans, boxes, bags and composite packagings, working toward a design registration rather than a shipping report.

The standard has two halves. Part 1 covers the design, testing and manufacture of UN standardised containers in Canada. Part 2 covers how a shipper then selects and uses them. Where the standard and the Transportation of Dangerous Goods Regulations disagree, the Regulations win.

Packing group maps to a marking letter, and the letter sets how hard the container is tested.

The letters nest. A container qualified to X may be used for packing groups I, II and III. A Y covers II and III. That is why manufacturers often test above their immediate requirement: one qualification programme at the higher level opens more of the market than a cheaper one at the level they happen to need this year.

Your container code decides the test set. Not every container gets every test.

• Drop. Run to ASTM D5276 onto a rigid, non-resilient surface, at a height set by your packing group and, for denser liquids, by the relative density of the contents.
• Compression resistance, the stacking test. Under constant load or constant force, calculated from the gross mass and the container height.
• Internal pressure. Liquids only. Hydrostatic, held at a pressure derived from the vapour pressure of what the container will carry.
• Leakproofness. Liquids only, under water and under air pressure. This one applies to production containers as well as prototypes, so it recurs rather than being a one-off.
• Water absorptiveness, the Cobb test. Fibreboard only, and it is the test people forget when they scope a 4G box.

Plastic containers get dropped twice over. Plastic drums, plastic jerricans, solid plastic boxes and plastic composites are conditioned and dropped at ambient temperature and again at low temperature. That is two full sets of specimens rather than one, and it is the most common way a TP 14850 programme gets under-quoted.

Some stacking tests run for weeks, not a day. Most containers hold the stacking load for a day. Plastic drums, plastic jerricans and certain composite packagings holding liquids hold it for 28 days at raised temperature. That is four weeks of chamber occupancy, and it decides your delivery date rather than your price. Establish the container code before anyone commits to a schedule.

There is also a day of dead time built into the standard: removable-head containers for liquids cannot be drop, leak or pressure tested until at least 24 hours after they are filled and closed, so the gaskets can relax.

TP 14850 does not define its own atmospheres. It calls ASTM D4332 for ambient, low temperature and high temperature conditioning, with paper and fibreboard containers going to ASTM D685 or TAPPI T402 instead.

TP 14850 is on Megalab’s A2LA ISO/IEC 17025 scope, and so is ASTM D5276, the drop method behind it. The conditioning that precedes every one of the five tests runs to D4332 in the same chambers. The chambers and the drop capability behind them are in our own building in Aurora, so a TP 14850 report from us is accredited data.

Being a Canadian lab matters more here than it does elsewhere in packaging. TP 14850 is a Transport Canada requirement, and sending containers across a border to be tested against it adds freight, customs paperwork and days to a programme that is already long.

Six things:

• The container code, for example 1A1, 3H1, 4G or 6HA1.
• The packing group you intend to mark, X, Y or Z.
• Whether it carries a solid or a liquid, and the relative density if liquid.
• The gross mass as shipped and the container height.
• Whether the design is new, reconditioned or remanufactured.
• Whether you want support toward the registration file or just the test data.

From that we confirm which of the five tests apply, how many specimens each needs, the conditioning stages and the real schedule, then quote it. If your design is a variation on one already registered, tell us, because the standard permits some variations without repeating the whole programme and that is worth checking before you pay for one.

The methods behind TP 14850 have pages of their own: ASTM D5276 drop testing and ASTM D4332 conditioning.

If what you actually need is proof that a packed product survives distribution rather than qualification of a container design, that is a different programme: ISTA procedures for a fixed published sequence, or ASTM D4169 where the route needs describing. Everything sits under package testing services.