Sourcing guide · Specifications
The chair specs that
predict durability
Two chairs can look identical and fail in completely different ways. These are the line items worth reading twice on any quotation — and the questions that expose them.
Start with the part that fails first: the gas lift
Gas lifts are classed by wall thickness and durability. Class 3 is the common commercial grade; class 4 uses thicker tube walls and is specified for heavier users and higher duty cycles. If a quotation says only "gas lift" with no class, assume class 2–3 until the factory confirms in writing.
- Class 3: standard office duty, typical for general task seating.
- Class 4: heavier duty; ask for it in 24/7 control-room, hospitality or heavy-user applications.
Foam density: the number that decides how a chair feels in year three
Foam is sold by density (kg/m³), not by thickness. A thick slab of low-density foam feels generous in a showroom and collapses within months. For seat cushions in commercial seating, higher density is what keeps the shape:
- Low density (under ~25 kg/m³): short-life, light-use only.
- Mid density (~30–40 kg/m³): typical commercial task seating.
- High density (45 kg/m³ and up): heavy duty, executive and 24/7 use.
Also ask whether the seat uses moulded foam or cut foam. Moulded foam holds its edge shape far better and is worth specifying on anything customer-facing.
Mesh: not all mesh is the same material
"Mesh back" can mean anything from a stiff nylon weave to a multi-layer elastomeric membrane. Ask for the material composition and the country of origin of the mesh; the price difference between grades is large and it shows up in sag and comfort within a year.
Base, casters and mechanism
| Component | What to specify |
|---|---|
| Base | Nylon (light duty) vs aluminium or polished steel (premium, heavier load) |
| Casters | Hard casters for carpet, soft/quiet casters for hard floors; check load rating per caster |
| Mechanism | Tilt only, synchro-tilt, or multi-position lock; weight-adjustable tension is the premium tier |
| Armrests | Fixed, height-adjustable, or 4D (height/depth/width/angle) — 4D is the usual spec on ergonomic models |
Test standards: BIFMA and EN 1335
Two standards come up constantly in tenders. BIFMA (ANSI/BIFMA X5.1 for general-purpose office chairs) is the North American benchmark; EN 1335 is the European standard for office work chairs. Certification is granted to a specific model by a testing laboratory — so the correct question is not "are you certified?" but "which model numbers hold which certificate, and can you send the scan?"
On factory quality systems, ISO 9001 is worth checking, but a certificate tells you the factory has a process, not that your order will be inspected. That is what pre-shipment inspection is for.
A specification list you can send to suppliers
Copy this into your RFQ: model reference · gas lift class · foam density (kg/m³) and moulded/cut · mesh material and grade · base material · caster type and load rating · mechanism type · armrest type · weight rating · applicable test standard · warranty terms · packaging method and carton CBM. Suppliers who answer all of it in writing are the ones worth progressing with.
Want a comparable spec sheet for a specific model? Browse the catalogue or open a model page and ask us on WhatsApp — we reply within 24 working hours.
Frequently asked questions
What is the difference between a class 3 and class 4 gas lift?
Class refers to the wall thickness and durability of the pneumatic cylinder. Class 3 suits standard office duty; class 4 is heavier duty and is usually specified for heavy users, hospitality or 24/7 environments.
What foam density should an office chair seat have?
As a working guide: under ~25 kg/m³ is light-use only, ~30–40 kg/m³ is typical commercial task seating, and 45 kg/m³ and above is heavy duty or 24/7 use. Ask for moulded foam rather than cut foam on customer-facing models.
Does BIFMA certification come with every chair?
No. Certification is issued per model by a testing laboratory. Ask the factory which model numbers hold which certificate and request a copy — a general claim of certification is not evidence.
What should I include in a chair RFQ?
Model reference, gas lift class, foam density and type, mesh grade, base material, casters, mechanism, armrests, weight rating, applicable test standard, warranty, and packaging with carton CBM.
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