Building
Regulations Advisory Committee Working Group Review of ADB.
The Review of Approved Document B was finally published after
a two year delay on 20 January 2000. Our
response to the updated guidelines follows below.
Building
Regulations remain a key part of the FSDG political agenda. Please
contact the Secretariat for more information on current activities.
The Fire Safety Development Group's
Response to Approved Document B (2000 edition)
The
Fire Safety Development Group has become increasingly concerned
at the relaxation in levels of fire protection in the Building
Regulations. This culminated in the changes enforced in the 1992
version of Approved Document B. The 2000 version offers us little
more comfort.
We
also take this opportunity to answer to the Government's response
to the Environment, Transport and the Regional Affairs Select
Committee into fire spread via external cladding systems published
on 29 March 2000. In our opinion several recommendations made
by the select committee and subsequently endorsed by the Government
might sensibly have been included in the revised Approved Document
B published in January this year.
General
Comments
Whilst
we realise Approved Documents are theoretically for minimal guidance
purposes, in practice they are taken to indicate the required
level of fire protection. The FSDG also challenges the underlying
assumption that the Building Regulations exist simply to protect
lives rather than lives and property. The 1985 version of Approved
Document B provided a level of fire protection sufficient for
both life safety and property protection. We therefore urge the
DETR to consider the socio-economic cost of fire damage in the
UK.
The
FSDG believes fire safety in buildings is achieved by the correct
use of a combination of "add-on" active and "built-in" passive
fire protection methods. The "trade off" concept introduced in
the 1992 version has yet to be supported by research. In the FSDG's
judgement there will be a serious fire, possibly involving injuries
and loss of life, directly attributable to the changes introduced
in 1992. Recommendations to counteract trade-off are referred
to in our consultation response in the proposed amendment to table
A2. BRAC ignored our suggestions.
The
FSDG welcomes some of the changes in Approved Document B, most
obviously the reduction to compartment size from 4,000 sq m to
2,000 sq m for retail premises and inclusion of the new Appendix
F on sandwich panels. However, even the appendix perpetuates the
misconception that the panel problem is limited only to internal
structures. Furthermore, the appendix has no minimal guidance
attached to it.
We
are also disappointed at the omission of guidance to combat smoke
emissions and resultant toxicity.
The
FSDG can therefore offer only a guarded welcome to the revised
document.
Specific Comments
We
would make the following specific comments that appeared in our
consultation response and seem to have been overlooked by BRAC
(page references given refer to the 1997 consultation paper):
1.
Page 7 - Materials and workmanship
The
FSDG suggested that the end of the first paragraph should be extended
to include -
"Proper
materials will be those shown to perform in a satisfactory manner,
during the expected lifetime of the building"
We
supported and welcomed the introduction of references to product
and installation conformity schemes, believing them long overdue.
However, we pointed out that the reference to longevity of fire
performance does not necessarily follow, whereas improved consistency
and quality of work should occur.
2.
Page 10, paragraph 0.13 - add item (e)
The
FSDG urged consideration for the safety of fire-fighters and emergency
workers entering a building on fire to carry out search and rescue
operations in accordance with Fire Precautions (Workplace) Regulations
1997, No. 1840, and in due regard to the attendance and mobilisation
times required from them.
3.
Page 50 - Shops: general
Cafes
We agreed with the intentions of the proposal, but believed
the guidance should be made for all Purpose Groups containing
cafes.
Store
Rooms in Shops
We
supported the proposals, with the exception of the level of fire
resistance required. The cost of higher resistance is negligible.
Our proposals were listed in a redraft of Appendix A.
4.
Page 66, paragraph 5.35 - Protected circuits
The
FSDG suggested the addition of the following new paragraph:
"An
acceptable alternative is to use non fire rated cables enclosed
in a fire resisting enclosure, where the circuit integrity is
maintainable under BS476 Pt20 heating conditions."
The
reference to small-scale test BS6387 on a short length of cable
may only provide a short time in a real fire. A more realistic
test would be to expose a long run of cables with fittings and
supports. Evidence supporting this view can be found in work reported
by BRE in the past few years.
5.
Page 67, Mechanical ventilation and air conditioning systems
We
proposed the addition of the following paragraph:
"Any
ductwork system, including a smoke extraction system, should be
able to satisfy the requirements of BS476 Pt24 if it passes through
a compartment wall or floor."
6.
Page 100, diagram 41 - Pipes penetrating structures
The
FSDG suggested an additional comment to the effect that the pipe
and sleeve should be adequately supported on each side of the
wall - fire protected hangers should be included.
7.
Page 101, paragraph 10.14 - Fire-stopping
The
comments should have been limited to paragraph 1. The remainder
should have been deleted. Such comments may contribute to repeated
misapplication of materials.
8.
Page 132, section 17 - Fire-fighting shafts
The
reduction of fire resistance provisions for buildings fitted with
sprinklers is based on supposition of the operability, maintenance
and durability of water supplies. For these reasons paragraph
17.7 and table 20 should have been deleted. The content should
not presuppose favourable results from a PTI project then believed
to be underway at BRE.
9.
Page 136-7 - Venting of heat and smoke from basements
The
point of passage of smoke outlet systems through compartment walls
and floors should be rated to BS476 Pt 24 to avoid spread of a
fully developed fire. The FSDG proposed that diagram 59 should
be extended to illustrate this popular occurrence. Those that
remain within a compartment, as in the proposed diagram 59, may
have lower fire resistance levels.
10.
Page 162, diagram C5 - Height of top storey in building
The
diagram made reference to the height of the top storey. We suggested
the height be increased to take in the roof level whenever it
supports external services plant equipment.
11.
Page 167, appendix E - Definitions
The
FSDG felt additional definitions for fire insulation and fire
integrity should have been included to assist with ambiguities
in the text over the word "integrity". Loose reference to BS 476
is inadequate. Differentiation between cavity, smoke and fire
barriers should have been included to reflect day-to-day construction
problems and abuses.
Approved
Document B & the Select Committee Inquiry into Fire Spread
in Buildings via External Cladding Systems
The
Minister is incorrect to claim in his response to the Select Committee
that no suggestion was made during the review of Approved Document
B proposing that the guidance given with respect to external cladding
was insufficient or, if followed, was liable to compromise fire
safety.
In
our comments concerning Section 12 of the consultation paper -
Construction of External Walls - we state:
"The
combustibility requirements of Diagram 44 (see proposals to amend
Approved Document B of the Building Regulations - December 1997)
for the external surfaces of walls need substantial revision to
avoid fire spread up the external surface of a building."
From
what we have learnt about the fire at Garnock Court, Irvine in
June 1999, the problem was of this very nature.
We
go on to say:
"There
is extensive dependence on inadequate small-scale tests for the
guidance offered - despite the realisation of the limitations
of these small scale tests. ISO TC 92 is recommending large-scale
tests to overcome these inadequacies. For example, fire emergent
from buildings can and have caused widespread collapse of the
entire render system onto fire fighters and others in the vicinity
of the building, when applied over combustible insulating materials.
The continuing dependence on Class 0 surfaces as the basis of
guidance is entirely inappropriate."
Our
redrafting of Section 12.7 argues that:
"Substantial
modification is required to remove the hazards of contemporary
sandwich panels and built up systems containing combustible insulation
under Class 0 surfaces."
In
its response the Government also pledges to provide better guidance
on fire stopping between floors and to support adoption of a new
British Standard fire test for external cladding systems. The
need for external cladding systems to have cavity barriers or
be adequately fire stopped were highlighted by the Irvine fire
and the subsequent select committee inquiry. However, it was also
set out in FSDG's re-draft of Section 9 of Approved Document B
(see paragraphs 9.1, 9.2 (a) and (f), as well as 12.4) submitted
to the DETR during 1997.
The
fact that Approved Document B (2000 edition) took little account
of comments submitted by FSDG provides solid evidence that BRAC
has dubious understanding of fire problems.
The
Government has consequently missed an opportunity to amend building
regulations to ensure external cladding is fire safe.
The
BRAC Consultation Process
Our
reservations are therefore not only limited to alterations to
the document. A more fundamental area of concern is the consultation
process itself. The FSDG analysed 176 of the 200 responses to
the consultation paper. Respondents were required to express their
opinion in a "tick box" method. This closed question approach
fundamentally restricted the remit and scope of the consultation
process. So serious were these restrictions, the FSDG responded
by re-writing the entire document to provide a submission of sufficient
detail.
Many
other organisations were unable to commit a similar level of resource,
and therefore simply made no comment on a large proportion of
the proposed changes. We therefore challenge the DETR assumption
that a no comment response can be taken as tacit acceptance of
the proposals. A more accurate interpretation is that some respondents
did not know how or where to respond fully. In our judgement the
consultation process was dangerously exclusive and limited genuine
analysis and debate. We can only assume therefore that the intention
was simply to appear to consult, rather than to actually to do
so.
There
are profound implications of ignoring or restricting the evidence
given by experts. One example of this concerns fire-fighting ladders.
The FSDG endorsed the Fire Brigade Union's comments concerning
the height of buildings compared to the height of ladders on appliances.
That comments of a public service nature such as these were overlooked
beggars belief, and must call into question how responses to the
consultation paper were assessed.
The
FSDG welcomes the commitments made by representatives of the Building
Regulations Division at the All-Party Parliamentary Fire Safety
Group inquiry into Approved Document B in February this year.
These include the creation of working groups to consider various
aspects of the Building Regulations at the next review stage.
This is a significant step forward and may begin the process of
mitigating some past mistakes.
In
Summary:
Although
Approved Document B (2000 edition) offers some areas of encouragement,
the FSDG is disappointed it fails to take more robust steps to
tackle "trade-off". We also harbour reservations about the consultation
process and the ability of BRAC to guarantee fire safety standards.
We hope our recommendations to address these shortcomings will
be acted upon prior to the next revision of Approved Document
B.
