Printable small parts tester

The official cylinder, drawn to size

The US rule for toys intended for children under 3 is short. A toy, and any part that can come off it, must not be “small enough to fit entirely within a cylinder” with the dimensions in Figure 1 of 16 CFR 1501.4. The cylinder is 1.25 inches across inside. Its floor slopes, so it is 1 inch deep on one side and 2.25 inches on the other. The rule says the inch figures govern; the metric ones printed next to them (31.7, 25.4 and 57.1 mm) are approximations, so this template uses the exact conversions: 31.75, 25.4 and 57.15 mm.

The test itself, in 1501.4(b): put the part in “without compressing it”. If it fits entirely in the cylinder in any orientation, it fails. If the whole toy doesn’t fit, it goes through drop, torque and tension tests, the “use and abuse” tests in 16 CFR 1500.51 and 1500.52, and every piece that breaks off is tested the same way. Paper, fabric, yarn, fuzz, elastic and string that come off are left out.

How to print it at the right size

1. Choose your paper and press Print at 100%. In the print window, set the scale to 100% or “Actual size”, never “Fit to page” or “Shrink to fit”. Card stock holds its shape better than paper.
2. Measure the black 50 mm bar with a ruler. If you only have an inch ruler, use the 2 in bar.
3. If the bar isn’t 50 mm, type what it measures into the box above. The tool works out the custom scale to set, for example 104.2% for a bar that measured 48 mm. Print again and re-measure.
4. Cut out the tube wall on the solid line, curl it into a tube with the printed rim at the top and glue the tab behind the other end. Fold up the tabs of the oval floor and glue it inside the wavy bottom edge, so that it slopes at 45°.

The wavy edge is not decoration: when a cylinder is cut by a sloping plane and unrolled, the cut becomes a wave. The highest point of the wave is the 25.4 mm side and the two ends are the 57.15 mm side, so the floor ends up exactly where it is in the official drawing.

How to use it

1. Gather every loose piece and every piece that could come off: wheels, eyes, caps, buttons on the toy, accessories, batteries.
2. Drop each one into the tube without pushing. Turn it and try again end-on and lying on the slope. If any way fits entirely below the rim, treat it as a small part.
3. For a quick check without building the tube, use the gauge card. A piece that passes through the 31.75 mm opening and is shorter than 25.4 mm in that direction would fit the cylinder. Between 25.4 and 57.15 mm long, it depends on the slope, so build the tube.
4. Try every ball in the 44.45 mm hole. A ball that drops through under its own weight is a “small ball”: banned in US toys for under-3s even when it is too big for the cylinder.

Worked examples

A toy tea set for a 2-year-old. The cups and the 9 cm spoons don’t fit, but the little sugar cubes, about 2 cm on each side, drop straight in. That set isn’t for under-3s; a set without the cubes, or with large pieces, is.

A 40 mm bouncy ball. It is wider than the 31.75 mm opening, so it passes the small-parts test. It drops through the 44.45 mm hole, though, so in the US it is a small ball: banned in toys for under-3s and labelled “Not for children under 3 yrs.” for older children.

A soft toy’s fabric bow. Squash it and it fits, but the test says without compressing, and fabric that comes off is left out of the cylinder test anyway. Check that the bow is sewn on well, and look for small hard parts, such as plastic eyes, underneath it.

What a paper tester can’t tell you

Paper bends and stretches, and the real fixture is a rigid cylinder used after the drop, twist and pull tests. So use this template to decide what to keep away from a young child, not to decide that a toy passes. If you make or sell toys, a home template is no substitute for testing: toys for children 12 and under must be tested and certified to the US rules.

Some things are exempt from the cylinder test altogether, including balloons, books and other paper articles, crayons and pens, children’s clothing and accessories such as buttons, and modelling clay (16 CFR 1501.3). Exempt is not the same as safe: uninflated or broken balloons can choke or suffocate a child, which is why every latex balloon carries a warning for children under 8.

The toilet-roll test: what’s true

Many parents are told that anything fitting through a toilet-roll tube is a choking hazard. The US Consumer Product Safety Commission has said that some parents use a toilet paper roll as a practical alternative, but that the roll is wider and longer than the official tester. So a tube flags more things than the real test does, which errs on the cautious side, but it can’t tell you whether a toy meets the rule.

The bigger catch is what neither test sees. Balloons are exempt from the cylinder, a small ball can be too big for the cylinder and still be dangerous, and button batteries and magnets do their worst damage after they are swallowed, not by blocking the throat. Check those with the age checker or the button battery checklist.

Common mistakes

• Printing with “Fit to page”. The sheet shrinks a few per cent and the opening comes out too small. Always measure the 50 mm bar.
• Testing only the whole toy. The rule is about every part that can come off in normal play or rough handling.
• Pushing a piece in. The test is “without compressing”: let it drop or rest.
• Forgetting the slope. A part 40 mm long fails if it fits lying along the slanted floor.