BS 5852 Crib 5: UK Commercial Furniture Flammability Standards

BS 5852 (Crib 5) stands as one of the most critical fire safety standards for the commercial furniture industry in the UK. For manufacturers exporting to the UK or supplying international hotel projects, this is a compliance threshold that cannot be ignored.

The UK has what is widely recognized as the “world’s strictest” furniture flammability regulations. This guide provides an in-depth analysis of the BS 5852 technical details, the specific “Crib 5” testing process, and how to ensure your products qualify for Medium Hazard environments in the British market.

What is the BS 5852 Standard?

BS 5852 (Full title: Methods of test for assessment of the ignitability of upholstered seating) is the primary standard used to assess whether furniture materials will continue to burn when exposed to an ignition source.

It does not just test the fabric alone; it evaluates the three key components of soft furniture:

• Upholstery Fabrics: The outer cover material.
• Filling Materials: The foams or padding underneath.
• The Composite: The combined structure of fabric + foam.

Core Ignition Sources: From Source 0 to Source 7

BS 5852 defines 8 ignition source levels of varying intensity. In commercial applications, the three most critical sources are:

• Source 0 (Cigarette Test): Simulates a smouldering cigarette. This is the minimum baseline for all furniture (domestic and commercial).
• Source 1 (Match Test): Simulates a match flame applied for 20 seconds. This is mandatory for domestic (home) furniture.
• Source 5 (Crib 5 Wood Crib Test): The Gold Standard for Commercial Markets. It simulates a higher intensity flame (similar to a burning pile of newspapers) and is mandatory for hotels, offices, and public spaces.

Deep Dive: What is the Crib 5 (Source 5) Test?

The term “Crib 5” comes from the specific wooden structure used as the ignition source in the test. Compared to a cigarette or small flame, it generates significantly higher heat and burns for longer.

1. The “Crib” Construction

Testers use a stack of 20 pine battens, glued together to form a “Crib” structure approximately 40mm high, resembling a small lattice or “Jenga” tower. This crib is placed at the junction between the seat and the backrest.

2. The Rigorous Process

• Accelerant: A specific amount (1.4ml) of Propan-2-ol (Isopropanol) is added to the lint at the base of the crib as an accelerant.
• Ignition: The crib is lit, producing a flame and heat output far greater than a match, effectively simulating furniture being ignited by arson or accidental debris.

3. Pass/Fail Criteria

To pass the test, the material composite must meet the following conditions:

• No Flaming: All flames must self-extinguish within 10 minutes.
• No Smouldering: There must be no progressive smouldering (burning without flame) inside the foam 60 minutes after ignition.
• No Burn-Through: The fire cannot burn through the full thickness of the filling or reach the edges of the test rig.

Regulatory Compliance: Scenarios & Industry Requirements

Crib 5 is the entry ticket for UK “Medium Hazard” environments. According to the BS 7176 specification, the following sectors must use Crib 5 compliant furniture:

• Hospitality & Resorts: Hotel room chairs, lobby sofas, upholstered headboards.
• Food & Beverage: Restaurant seating, bar booths, nightclubs, and lounges (areas requiring resistance to cigarettes and small open flames).
• Healthcare: Hospital waiting areas, nursing home patient chairs.
• Public Buildings: Offices, airport VIP lounges, theatres, and educational institutions.

How to Select Crib 5 Compliant Fabrics (Material Guide)

Not all materials can withstand the intense heat of a wooden crib. Understanding fibre characteristics is crucial for procurement. Below is a breakdown of common materials:

Material Type	Crib 5 Capability	Notes
FR Polyester	✅ Usually Passes	The most cost-effective choice for hotel interiors. e.g., Begoodtex IFR Furniture Fabrics.
Modacrylic	✅ High Pass Rate	Inherently flame retardant fibre with stable performance.
Aramid	✅ Easily Passes	High-performance industrial-grade FR material.
Normal Polyester	❌ Fails	Melts and drips easily. Must undergo chemical back-coating to pass.
Natural Cotton/Linen	❌ Fails	Highly flammable. Requires strict chemical impregnation/treatment.

Recommendation: For high-traffic commercial spaces, we recommend prioritizing IFR (Inherently Flame Retardant) Polyester (such as the Begoodtex collection). These fabrics pass Crib 5 naturally without requiring chemical back-coating, avoiding the risk of coating degradation over time while maintaining a softer touch.

Global Comparison: BS 5852 vs. EN 1021 vs. US Standards

British standards are renowned for their severity. Here is how BS 5852 compares to other mainstream international standards:

Standard System	Test Intensity	Covers Crib 5?
BS 5852 Source 5 (UK)	⭐⭐⭐⭐ (High)	Yes (Wood Crib Test)
EN 1021-1/2 (EU)	⭐⭐ (Medium)	No (Equivalent to Cigarette/Match only)
CAL TB 117 (USA)	⭐ (Low)	No (Primarily Cigarette/Smouldering)

Frequently Asked Questions (FAQ)

Q: If a fabric passes EN 1021 (EU Standard), will it pass BS 5852 Crib 5?

A: Most likely not. EN 1021 only includes cigarette and match tests. Its heat output is significantly lower than the Crib 5 wood crib. A Crib 5 test generates approximately 20 times the heat of a match test.

Q: Does domestic (home) furniture need to pass Crib 5?

A: No. UK law (The Furniture and Furnishings Fire Safety Regulations) requires domestic furniture to pass Source 0 (Cigarette) and Source 1 (Match). Crib 5 is specifically for Commercial and Public environments (Medium Hazard).

Q: Is the Crib 5 test performed on the fabric alone?

A: No. BS 5852 is a “Composite Test.” Even if the fabric is flame retardant, if the foam underneath is standard non-FR foam, the test will likely fail. The fabric and foam must work together to prevent ignition.