Assessing educational seating

Explaining how chairs are tested in accordance with EN 1729.

When supplying seating (and tables) to the education sector, there are two key standards with which to demonstrate compliance that will often be included as part of the contractual agreement. These are i) EN 1729-1:2015 – ‘Furniture – Chairs and tables for educational institutions. Functional dimensions’, and ii) EN 1729-2:2023 – ‘Furniture – Chairs and tables for educational institutions. Safety requirements and test methods’.

Part 1 of EN 1729 is based on the principle that seating should be designed to promote good posture. The previous (2006) and latest revisions include a set of specified dimensions (and angles) for such characteristics as seat height, seat width, position of the lumbar region, height of arm rests, angle between seat and back, and more. These are either given as minimums, maximums or a range for each characteristic. Once a set of dimensions has been measured, the chair can be classified between size marks ‘0’ and ‘7’, with 0 being the smallest (see table 1). These size marks are indicated by a colour-coded label or some coloured component on the furniture. The smallest individual dimension (or angle) found dictates the size classification, even if all the other dimensions found comply with larger sizes.

Table 1: Size mark guide
Size mark	Colour code	Indication of age range
0	White	Less than 4 years
1	Orange	3 to 4 years
2	Violet	4 to 5 years
3	Yellow	6 to 7 years
4	Red	8 to 10 years
5	Green	11 to 13 years
6	Blue	14 to 18 years
7	Brown	18 years plus

Part 2 of the standard is used to ensure that the seating meets a set of minimum requirements for safety, stability, strength and durability. The quantity, severity and position of the various test loads and cycles depend on the size mark determined from the measurement results of part 1.

Both standards were first published in 2001. However, the revision to part 1 (dated 2015) has seen the implementation of some significant changes.

Significant changes

Part 1 – The most important change is how the seat height, seat angles, seat depth, armrest height and distance from backrest to the front edge of the armrest are measured. For size marks 3 to 7, a special jig called the ‘school chair measuring device’ (SCMD) is now used instead of basic measuring tools. This consists of a base plate which is positioned on the seat surface, and a vertical arm which is positioned against the back rest. These are joined to each other with a pivot and slide mechanism. Both the base plate and the vertical arm have various adjustable pins that are used to correctly position them on a particular size and shape of chair. The SCMD is positioned according to the form and position of the lumbar region of the back rest (described in the standard as point ‘S’ or the ‘most forward point of the back rest’) and the highest point of the seat surface. Measurements are taken and correct form is assessed from the adjustable pin positions, the angles of the base plate and vertical arm, and other specific protruding elements.

In terms of the actual dimensional requirements, the most significant change is how the width of the back rest is measured. Previously, it was measured at the maximum width, whereas the 2015 version requires it to be measured between the ends of the horizontal line that passes through point ‘S’.

In 2023, part 2 was updated to include the following:
1) Extension of scope to include safety requirements and test methods for kindergarten, childcare institutions and early-years education settings.
2) Additional durability requirements for single-column chairs.
3) Additional consideration for chairs with armrests.
4) Clarification of seating loading points and back loading points.
5) Amendment of some loads and forces.
6) Modification of Annex A (informative) test method for determination of stability of chairs placed on tabletops.
7) Inclusion of corner stability test for chairs.
8) Inclusion of requirements for auxiliary writing surfaces which are integral parts of chairs.
9) Additional safety requirements for chairs sizemark 0 to 3.

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