EN 1335 Type A, B and C: Not the European BIFMA
EN 1335 is three documents, and the Type A, B and C letters describe how much the chair adjusts, not how well it is built. What the rating does and does not say.
EN 1335
Office Chair Recline Angle Explained: 90, 120, 135, 180
A recline number means nothing until you know what it is measured from. What 90, 120, 135 and 180 degrees count, and where the 135 figure came from.
Office Chair Specifications Explained: Every Spec Decoded
A line by line guide to office chair specifications: which numbers are standards-backed, which are marketing words, and what a listing never tells you.