(Updated) SS 299:2021 Updates - Fire Resistant Test Standard

Updated on Sep 28, 2023

In our previous Keystone Academy blog, 'Fire resistant test standards-explained!'. we introduced the differences among the 3 common LSZH FR test standards. In Singapore, FR cables undergo tests required by the Singapore Standard (SS), SS 299. This standard only applies to power and control cables. Following a grace period implemented by the Singapore Civil Defence Force, the revised version (SS 299: 2021) came into effect on 1 September 2023, extending the voltage range to 600/1000 V.

SS 299:2021 standards specify the requirements of FR cables in terms of characteristics required to maintain circuit integrity. Additionally, another criterion is the ability to reduce flame spread, emit low levels of smoke, and emit halogen-free gas during a fire. This is essential as it ensures that the power supply can be sustained in order to power life-saving electrical installations, such as fire alarms, smoke detectors, PA systems, and emergency lighting, even in the event of a fire.

SS 299:2021 comprises other testing standards that address physical and electrical cable requirements. According to the updated FR Test standard, passing Protocols C, W, and Z is mandatory for FR cables to be fully compliant. It is noteworthy that other protocols including A, B, S, X, and Y from previous regulation a considered obsolete. Prior to 2021, FR cables were required to pass Category C, while Categories W and Z were optional.  

A Brief history of SS 299: 2021 

Before SS 299:2021 was introduced, the standard was known as SS 299: Part 1 and established in 1985. It fully incorporated British Standard (BS) BS 6387 for cables up to 450/750V for PVC and rubber cables. However, in 1994, BS 6387 shifted to conventional cable construction, excluding PVC and rubber cables. Consequently, in 1998, SS 299: Part 1 underwent its first revision, adopting conventional construction while increasing the voltage rating to 600/1000V. In 2008, an amendment aligned reference standards with International Electrotechnical Commission (IEC) standards.

BS 6387 saw no further updates, prompting a Singapore workgroup in 2013 to confirm SS 299 Part 1: 1998's validity. Meanwhile, in 2013, BS 6387's 3rd edition raised voltage ratings to 600/1000V, presenting test methods rather than specifications. This prompted the Singapore working group to decide in favour of retaining SS 299 as a specification. To do so, they planned to reintroduce physical and electrical components, making cable specifications part of the requirements. The focus will be placed on low smoke, halogen-free materials, and flame spread capability, aligning with Singapore Standards for robust fire-resistant cables.

Fire-resistant tests: SS 299: 2021 (from 23 Sept 2021 onwards)

Fire-resistant tests: SS 299-1:1998 (before 2021)

• Resistance to fire alone (Category A, B, C, or S)

• OPTIONAL: Resistance to fire with water (Category W)

This is meant to simulate fire in the presence of activated sprinkler systems.

• OPTIONAL: Resistance to fire with mechanical shock (Category X, Y, or Z)

This is meant to simulate fire in the presence of disturbances such as falling debris.

Check in with us to learn more about how we can help you maintain circuit integrity while delivering energy, or if you need further guidance on how the new regulation impacts your business. Our Sales team is ready to guide you through the transition.