The Haircutters Ltd
Client: The Haircutters Ltd
Location: Barrow-in-Furness, Cumbria
URL: None available
Project: Fire Safety Engineering
Applications: EvaQ8, GSN, Avanade
Keywords: Evacuation Simulation, Claim, Argument, Evidence
`Review' undertook major refurbishments to extend their existing business from a
single room premises. The alterations required the conversion work to the two upper
floors. The final outcome would be a multi-functional establishment with the ground
floor remaining the hairdressers, the first floor a café and the top floor a beauty
clinic.
The owner, Gary Johnson, an experienced tradesman, Project Managed the conversion.
“My aim was to reduce the sub-contracting costs. Although I was aware of fire legislation
as a result of dealings with the local authorities and fire service, my appreciation
of the acceptable criteria and design solutions was limited”.
The alterations required a second means of escape to satisfy the Building Regulations.
The owner, wanting to add uniqueness and character to the premises, purchased a
spiral staircase for approximately £7K. “Unfortunately, upon consultation with the
council they refused me permission to install the spiral staircase as an alternative
means of escape. They explained why they refused and said nothing could be done
about it”. The refusal was due to the staircases non-compliance with the minimum
width in accordance with the Building Regulations, BS 5385 Part 2.
SOA were asked to evaluate the situation and develop an adequate design for the
means of escape and if possible utilise the spiral staircase. SOA considered the
use of the building, useable floor area and associated floor space factors to calculate
the maximum occupancy levels for the premises. Consequently, adequate MoE were then
designed based on the calculated occupancy levels.
These designs took into consideration the spiral staircase, occupancy levels, and
building layout and obstructions. Through empirical calculations and optimisation
of escape routes using the heuristic tool EvaQ8, SOA justified the spiral staircase.
The resulting justification highlighted that with the occupancy levels specified,
the design had adequate corridor protection, a large gantry preceding the spiral
stairs, minimal travel distances to exits and high staff to customer ratio to name
a but a few.
In addition, the resulting evacuation assessment, using evacuation software EvaQ8,
was able to demonstrate that the premises could be evacuated in less than two minutes.
This evacuation report was presented to the building control, justifying the design
solution using a claim/argument/evidence approach.
The building control authorities acknowledged the logical basis of the argument,
and with the supporting evidence agreed to allow the implementation of the spiral
staircase. Part of this process was an independent review by another authority
“Had SOA not been successful I would have had to purchase a purpose built external
staircase that would have cost me an additional £11K. This would have delayed opening,
left me with a spiral staircase that I could not use and an unattractive staircase
on the outside of my building. I have no doubt this success is due to SOA”.
The premises now retains it’s ‘design flair’ adding character and uniqueness to
the building exterior, satisfying the clients objective.
Claim - Argument - Evidence
What happens when building design does not strictly conform to the Building Regulations?
Is it simply the case that these regulations must be complied with all standards
and the proposed design altered? Alternatively, is it possible to satisfy the intent
of the regulations with a justified level of non-compliance?
The initial response from the authorities regarding any deviation from regulations
and standards is to err on the side of safety i.e. to require strict adherence to
the regulations. However, on occasion, the authorities have permitted the variation
but only where sound justification is presented. This article presents a methodological
approach to presenting such justification to the authorities.
SOA have demonstrated that a safety engineering approach, based on Claims-Argument-Evidence,
can be effective in justifying acceptable deviations from the letter of the regulations
whilst adequate safety measures are achieved inconsideration with meeting business
objectives.
This technique is fast becoming the standard method in risk based safety justification
viewed as being more effective for safer than prescriptive compliance such as build
regulations.
In support of these objectives, SOA provides a case study demonstrating how the
functional regulations and supporting guidance can be interpreted. In doing so,
this study illustrates the processes involved in allowing designers to justify alternative
solutions.
Variance:
Any variance to a regulation can be granted providing there is a sound argument
with sufficient mitigation to provide comparable levels of safety, demanded by the
regulations.
This does not mean you can openly flaunt the regulations, in fact, quite the opposite.
A compelling argument must be offered to demonstrate to the authorities that the
claimant is acting responsibly and with a duty of care. Importantly, this duty of
care is also extended to the granting authorities in permitting any variance to
a regulation. Evidence, therefore, is essential for both parties. Variance can be
best relayed to the authorities by following the Claim-Argument-Evidence approach.
Claim:
It is important to remember that Claims are not facts but rather, propositions that,
like in a court of law must be proven. Therefore, in order for any claim to stand
a chance of acceptance, it is necessary that supporting argument and evidence is
available.
Argument:
The Argument rationalises and justifies the claim based on the supporting evidence.
This goes beyond pure description and comprises an analytical discussion, demonstrating
the claims evidence.
Evidence:
The evidence is used as the basis of any argument. The evidence can use predicate
logic (deterministic), statistical analysis (probabilistic) or qualitative analysis.
The evidence is linked to the claim with an argument.
This paper is a high level explanation used to demonstrate the claims-evidence-argument
process and directed attention to a number of contingencies to which the responsible
persons should take into consideration. This approach, coupled with an appreciation
of the functional requirements of the legislation enables greater scope for innovative
solutions. The case study above highlights the successful implementation of this
approach.