Building Standards (Fire Safety) Review Panel International-Sub-Group minutes: February 2018

Attendees and apologies

Present

• Dr Paul Stollard, Chair
• Brian Ashe – Australian Building Control Board, Australia
• Brian Meacham – Meacham Associates (formerly Worcester Polytechnic Institute),USA
• IJsbrand van Straalen – Dutch research organization TNO
• Bill Dodds – Scottish Government
• Stephen Garvin – Scottish Government
• Colin Hird – Scottish Government

Items and actions

1. Welcome, agreed notes, apologies

The Chair welcomed members of the international sub-group of the Review Panel to the second meeting.

The notes from the first international sub-group meeting had been circulated and agreed in advance.

Apologies were received from Rainer Mikulits, Austrian Institute of Construction Engineering.

2. Research Methodology and Process

The research methodology and process were reviewed and the future method of working was agreed. It was accepted that this process is essentially one of expert review, with this international group adding a wider and independent perspective on the discussions the UK based Review Panel. A flow diagram was developed during discussion which summarised this and a copy is attached to these notes (Figure 1).

There was also a report on other works being undertaken by the Scottish Government, including the Review Panel on Compliance and Enforcement being chaired by John Cole and Fire safety regime work stream. It was agreed that international group members would receive the notes from these work streams as they become available.

There was discussion of other initiatives being undertaken by the UK government and in particular the Interim Report from the Dame Judith Hackitt review of Building Regulations in England.

In advance of this meeting the members had received the Agreed Notes from the second UK based Review Panel meeting (17 January 2018) and it was agreed that the review of these should form the basis of the meeting.

3. Conclusions from the earlier meetings

The members discussed and agreed with the views already expressed at both the UK based Review Panel meetings.

The current structure of functional standards supported with performance based or prescriptive guidance in the Technical Handbooks broadly works and should be retained. This was felt to be at the heart of the fundamental debate between those who wish for a “functional/performance” based system and those who prefer a “prescriptive” system. The Scottish system needs to concentrate on the functional/performance standards. However there is value in seeking to revise the wording, possibly including a little more text, maybe even numbers. There is also a need to ensure the system which exists, and its use, is fully understood.

There is a need to make some minor changes to the wording of individual functional standards to remove ambiguities and prevent deliberate evasion of the intention of the standards.

More work was felt to be needed on the Technical Handbooks to ensure they are clearer and understandable to the general public. Their role and limitations as guidance needs to be understood. There was lengthy discussion as to the possible value of making it clear within the Technical Handbooks that there are alternative “pathways to compliance “ with the functional standards, ranging from a very prescriptive, “crude and conservative” pathway, to a fully performance based “fire safety engineering” pathway. These could be considered as:

a. a very prescriptive, “crude and conservative” pathway, available for all to use,

b. a middle pathway, which combines engineering principles and prescribed requirements, within agreed bounds, for those competent to use it properly, and

c. a fully performance based “fire safety engineering” pathway, from first principles, available for those competent to use it properly, and verified via a body competent to verify fire safety engineered designs.

There was then more detailed discussion on the five substantive areas which had been discussed at the second Review Panel meeting.

4. Cladding, materials and testing (Standards 2.4 to 2.8)

It was agreed that the tests for reaction to fire in respect of a fire developing on, behind or within the façade of a building should not automatically be the same as those relating to fire spread on internal wall and ceiling linings.

The idea of alternative compliance pathways was discussed for these standards where:

a. the very prescriptive, “crude and conservative” pathway might be non-combustible or limited combustibility (Euro classes A1 and A2),

b. the middle pathway might be evidence from a BS8414 (and BR135), and

c. a fully performance based “fire safety engineering” pathway would still be available for those competent to use it properly.

There was lengthy discussion on how such alternative compliance pathways could be structured within the Technical Handbooks, how the introductory explanatory sections were made necessary reading, and how it might be possible to prevent ill-informed users just searching the handbooks without understanding to find paragraphs which seemed to support their designs.

It was also stressed that if alternative pathways were provided then their equality in satisfying the functional standards needed to be clarified. Each pathway would fulfil the Functional Requirements, but the very prescriptive, “crude and conservative” pathway would inevitably have some built in redundancy.

5. Means of escape (Standard 2.9)

It was agreed that designers must understand and make clear which escape strategy (“defend in place” or “total evacuation”) they were adopting.

The idea of alternative compliance pathways was discussed for these standards where:

a. the very prescriptive, “crude and conservative” pathway might be total simultaneous evacuation for every building,

b. the middle pathway might permit “defend in place” for certain buildings types (e.g., high-rise flats), when combined with other fire safety measures and assessed within an agreed approach, and

c. the fully performance based “fire safety engineering” pathway, which could involve a wide range of egress options (e.g., occupant use lifts, phased evacuation, etc.), when fully engineered by those competent to use it properly, and verified via a body competent to verify fire safety engineered designs.

There was a general feeling that at some point in the middle pathway where “defend in place” was the declared strategy for flats, there was a need for two stairs. This is partly to permit fire-fighters to be ascending while residents were evacuating.

On the issue of two stairs, when defend in place” is the strategy for flats, Australia has this as a requirement over 25m height.

There was some discussion on the wisdom, or otherwise of permitting designers to “mix and match” different compliance pathways for different standards. This is permitted in Australia. The consensus was that if the design is on a fully performance based “fire safety engineering” pathway, then it might be acceptable to revert to the very prescriptive, “crude and conservative” pathway for some standards, but that the reverse was not sensible. However, if the design began on the very prescriptive, “crude and conservative” pathway it was not sensible to permit departure from this for just one standard with which it was proving hard to comply.

6. Sprinklers (Standard 2.15)

The group agreed with the UK based Review Panel’s view that although sprinklers were valuable in tackling fires in the initial stages and limiting spread beyond the first materials ignited, they should not normally be installed to compensate for the removal of other fire safety measures.

The group did not approve of a “trade-off” mind-set, permitting sprinklers to justify a reduction in the number of stairs or a lower fire safety performance of the cladding. This linked back to the discussion on the integrity of the different compliance pathways and the independence of the different functional standards.

Australia does not at present require sprinklers in residential building below 25m. It is proposed to provide an option in 2019 for sprinkler protection of residential buildings over 3 storey’s.

There was agreement that the mandatory requirement to install sprinklers should be targeted to those buildings where they would be most beneficial. Trigger heights for any new requirement to install sprinklers were discussed and it was agreed that this requires further exploration.

7. Verification of fire engineering solutions

There was discussion of the mechanism which might be appropriate to verify fire engineering solutions and the group agreed with many of the points made by the UK based Review Panel, in particular that:

a. the construction industry would probably prefer the prescriptive guidance in the Technical Handbooks and wanted less reliance on fire engineered solutions.

b. on occasion the Technical Handbooks were being inappropriately used not as default guidance, but as a benchmark against which so-called fire engineering solutions were being inappropriately assessed.

c. consideration should be given to removing the option of pressurised escape stairs as there are questions over their reliability to keep smoke out of escape stairs and corridors. They would still remain possible as part of the compliance route for the fully performance based “fire safety engineering” compliance pathway.

d. moving the fire engineering community towards Building Standard Certification was a longer term strategy, which would be welcomed by the industry generally, but was considered to be at least five years away. The feeling was that moving too fast in this area might unintentionally introduce self-certification.

There was a discussion as to whether or not the scope of the Technical Handbooks should be reduced. The group agreed with the UK based Review Panel that the scope of the Technical Handbooks should be not so limited as to force designers to employ fire engineers when these were perhaps not necessary due to the relatively simple nature of the building. The group linked this to the concept of compliance pathways already discussed. They decided that while the very prescriptive, “crude and conservative” compliance pathway should be available for almost all buildings, it might prove restrictive. This might encourage designers to use alternative pathways and if they choose the fully performance based “fire safety engineering” compliance pathway they might well require specialist advice.

Therefore the group was sceptical about retaining some of the specialist guidance currently in the Technical Handbooks, which might not be comprehensive and might be insufficient to deal with all fire engineering issues (e.g. the annexes on hospitals and shopping centres).

On the issue of verification the group discussed the idea of a central “hub” which might be responsible for the handling complex buildings where the fully performance based “fire safety engineering” compliance pathway had been chosen.

While it was agreed that this issue has to be considered in conjunction with the Compliance and Enforcement panel, there was a view that it sat more comfortably with this Review Panel as it is so closely linked to the Functional Standards and Technical Handbooks.

8. Existing Buildings

This was discussed and it was agreed that for buildings in use the key issue should not be did it have a warrant at the time of construction, but is it safe in the use to which it is now being put. It was felt that the powers already available were probably sufficient and that it was a matter for the Scottish Government to decide when to use such powers.

9. Next meeting

The next meeting of the UK based Review Panel has been set as 11 April, therefore it was agreed that the international sub-group will aim to meet around the IRCC’s next meeting. A probable date for the sub-group’s meeting was identified as Friday 25 May.

As it was hoped that the public consultation might occur during the summer of 2018, the group agreed that the fourth meeting of the international sub-group might be able to be held in conjunction with the planned meeting of the IRCC during the first week of October 2018 (possibly on the 2nd).

Figure 1 - Research Methodology & Process.pdf

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