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Industry 4.0

Industry 4.0 in AEC, means to me a decentralized connection between the physical space and the cyberspace through global connectivity.

Comparison of ISO 19650 Part 2 and 3

UK BIM Framework (roadmap)

Exchange Information Requirements (EIR) term introduced by BS EN 19650 replace the PAS 1192 term Employer Information Requirements (EIR) on all projects where BS EN ISO 19650 compliance is required.

Lead Appointed Party

The term introduced by ISO 19650 typically describes the Tier 1 Main Contractor.

Federation Strategy

breakdown structure to help plan the production of information

Task Information Delivery Plan (TIDP)

schedule of information containers and delivery dates, for a specific task team

Model Production Delivery Table (MPDT)

An MPDT its old PAS 1192 term, the MPDT defines who produces what, when and to what level of detail.

Wiring in Protected Escape Route

Introduction

Compliance with fire safety regulations in Firefighting Cores is not just about passing inspections – it directly affects life safety and emergency response. This guide will help you meet the latest fire performance standards. With updates in BS 9991:2024 and BS 7671:2018+A2:2022, there are stricter fire performance requirements for cables, containment, and fixings within protected escape routes.

This guide will help designers, electrical contractors, and compliance officers ensure that wiring systems are installed correctly while meeting the latest fire safety standards.

Safe access for Fire Fighters and Safe evacuation in the event of Fire

Escape Routes
Protected Escape Routes
- Firefighting lobby
- Shaft or staircase of a protected escape route
- Protected lobby
- Protected corridor
- Protected stairway
Firefighting shafts

Key Fire Performance Requirements for Cables & Containment

Cables

✅ Must have an exposed surface rating of B-s3, d2 or better.

✅ If the cable does not meet this classification, it must be enclosed in fire-rated containment.

✅ Cables must not have junctions or connections inside the fire core (Regulation 422.3.5 of BS 7671).

Supports & Fixings

✅ Must be Class A1 (fully non-combustible) – e.g., steel brackets, supports, and anchors.

❌ Not Permitted: Plastic clips or composite fixings, even if fire-resistant.

Electrical Containment

✅ Cables must be routed in steel trays or conduits to prevent fire spread.

✅ Fire-stopping must be applied at all penetrations to maintain fire integrity.

🔑 Summary of Compliance Options:

✔ Option 1: Use cables that meet B-s3, d2 classification.

✔ Option 2: Fully enclosed non-compliant cables in metal containment (steel conduit/trunking).

Containment Systems Standards for Containment: Cables that do not inherently meet the required fire performance must be routed within containment systems that meet:
BS EN 50085 Series for cable trunking and ducting systems
BS EN 61386-1 for conduit systems
Practical Example: When using standard LV cables (which might not achieve B-s3, d2 ratings on their own), installing them in a steel conduit or fire-rated trunking system (certified per BS EN 61386-1 or BS EN 50085) can provide the necessary protection.

Understanding Fire Classifications

Class A1 Fixings (Supports & Brackets)

✅ Definition: A1 materials are non-combustible and do not contribute to fire.

✅ Examples: Stainless steel brackets, trays, conduits, and concrete anchors.

❌ Not Compliant: Plastic or composite materials.

B-s3, d2 Fire Classification for Cables

✔ B: Limited combustibility.

✔ s3: High smoke production.

✔ d2: Higher flaming droplet production.

✅ Cables meeting B-s3, d2 or better can be installed without containment.

✅ If a cable does not meet this, it must be fully enclosed in steel containment.

Under BS EN 13501-6 (the test standard used for cables under the Construction Products Regulation, CPR), cables are given a Euroclass rating such as:

Aca (non-combustible)
B2ca
Cca
Dca
Eca
Fca

with additional indicators for smoke (s1, s1a, s2, s3), flaming droplets (d0, d1, d2), and acidity (a1, a2, a3).

By contrast, BS EN 13501-1 (more common for general building products like wall linings) uses classes A, B, C, D, E, F along with s and d indices, e.g., “B–s3,d2.”

Although the notations look similar, the specific tests and criteria differ slightly for cables versus other building materials. Roughly speaking:

B2ca for cables is often considered on par or “better” than B–something for general construction products.
s1a (very low smoke release) is better than s3 (higher smoke release).
d1 (no sustained flaming droplets) is better than d2 (some flaming droplets allowed).

Hence B2ca–s1a,d1,a1 can be viewed as meeting or exceeding B–s3,d2 in practical fire-performance terms.

Cable Classification (example)

✅ FP600S

Prysmian FP600S (BS 7846-F120) meets the latest CPR Euroclass rating:

✔ B2ca–s1a, d1, a1, which is superior to B-s3, d2.

✔ B2ca: Higher fire resistance than B-s3.

✔ s1a: Very low smoke production (better than s3).

✔ d1: Minimal flaming droplets (better than d2).

Compliance with BS 9991:2024

BS 9991:2024 deals with fire safety in the design, management, and use of residential buildings. Where it references reaction-to-fire performance of cables (for instance, in escape routes or critical circuits), a B–s3,d2 or better classification is often cited.
Because FP600S is classified as B2ca–s1a,d1,a1, it satisfies a higher standard of reaction-to-fire than B–s3,d2.
As long as the cable is installed in accordance with the rest of BS 9991’s guidance (e.g., containment, fire-stopping around penetrations, circuit design, etc.), FP600S would be fully acceptable.

FP600S exceeds the fire performance requirements and is fully compliant with BS 9991:2024 when installed correctly.

✅ Other Multicore SWA Options

If for some reason FP600S is not suitable (cost, availability, or otherwise), you can look at alternative BS 7846-F120 or fire-rated SWA cables from other manufacturers—many now offer B2ca–s1,d1 (or s1a,d1) ratings. Examples include:

Draka Firetuf Powerplus (sometimes listed as B2ca–s1,d1,a1)
Nexans Fire-Performance Armoured cables meeting BS 7846-F120 & CPR B2ca

Always confirm with the manufacturer’s datasheet or DoP (Declaration of Performance) that the specific drum/batch of cable has the required CPR rating.

🔧 Installation Best Practices for Fire Compliance

To achieve full compliance, correct installation is essential:

✔ Use A1-rated steel supports (brackets, fixings, and hangers).

✔ Ensure cables are installed in steel containment if they do not meet B-s3, d2.

✔ Fire-stop all penetrations with rated materials.

✔ Coordinate with other MEP services to ensure all materials in the fire core meet fire classification requirements.

Fire-Stopping Considerations

✅ Seal all cable penetrations in fire cores with approved fire-rated seals or intumescent collars.

✅ Ensure that any joints or terminations in high-risk areas are enclosed in a fire-rated enclosure.

Quick Reference Table

Feature	Compliant Installation	Non-Compliant Installation
Cable Type	B-s3, d2 or better	Standard PVC cables
Fixings	Class A1 (fully non-combustible)	Plastic clips
Containment	Steel conduit or fire-rated trunking	Open cable routing
Junctions	None inside fire core	Connections within escape routes

🔍 Final Thoughts

With stricter fire regulations under BS 9991:2024, electrical installations within firefighting cores and escape routes must comply with enhanced fire classification requirements for cables, fixings, and containment.

Using BS 7846-F120 compliant cables like FP600S and ensuring correct installation methods will help meet compliance while maintaining fire safety in high-risk buildings.

📢 Need expert advice on selecting fire-rated cables, fixings, or containment systems? Contact us today!

📢 Need expert advice?

Wiring in Protected Escape Routes

Click to get in touch!

📖 References

BS 9991:2024 – Fire safety in residential buildings.
BS 7671:2018+A2:2022 – Requirements for Electrical Installations.
BS EN 60332-1-2 – Test for Vertical Flame Propagation.
BS EN 50085 & BS EN 61386-1 – Cable Trunking and Conduit Systems.
BS 7846-F120 – Fire-Resistant Armoured Power Cables.
BS 8519:2020 For fire-resistant power and control cables in life safety systems.

This guide is designed as a practical resource to help you achieve the highest fire safety standards in electrical installations. Stay safe and compliant

One Response

Olaitan Sofola says:

2025-02-21 at 2:53 pm

Thanks for sharing. This is highly informative.
I guess similar selection would definitely be applicable for critical systems designing and installation.

Reply

Blog
Digital Construction (electrical)

Wiring in Protected Escape Route

Introduction

Key Fire Performance Requirements for Cables & Containment

Cables

Supports & Fixings

Electrical Containment

🔑 Summary of Compliance Options:

Understanding Fire Classifications

Class A1 Fixings (Supports & Brackets)

B-s3, d2 Fire Classification for Cables

Cable Classification (example)

✅ FP600S

Compliance with BS 9991:2024

✅ Other Multicore SWA Options

🔧 Installation Best Practices for Fire Compliance

Fire-Stopping Considerations

Quick Reference Table

🔍 Final Thoughts

📢 Need expert advice?

📖 References

One Response

Leave a Reply Cancel reply

share this page

Blog Digital Construction (electrical)

Wiring in Protected Escape Route

Introduction

Key Fire Performance Requirements for Cables & Containment

Cables

Supports & Fixings

Electrical Containment

🔑 Summary of Compliance Options:

Understanding Fire Classifications

Class A1 Fixings (Supports & Brackets)

B-s3, d2 Fire Classification for Cables

Cable Classification (example)

✅ FP600S

Compliance with BS 9991:2024

✅ Other Multicore SWA Options

🔧 Installation Best Practices for Fire Compliance

Fire-Stopping Considerations

Quick Reference Table

🔍 Final Thoughts

📢 Need expert advice?

📖 References

One Response

Leave a Reply Cancel reply

share this page

Blog
Digital Construction (electrical)