VQB5642: PERFORMANCE CODES METHODOLOGY & STRUCTURE
WEEK 6: Practice Case Study Assignment
General Guidance
Answer the question. Look exactly at what is asked. Don’t just write down everything you know.
Try to put yourself in the position of an assessor – you aren’t designing you are assessing
Don’t take any reference or calculation on the face value – check it
Question 1
(Mainly what is given / you can infer, rather than what should be given)
1. < 25m (lesser DtS requirement)
2. 4 storey (not 5) and atrium connecting all floors
3. Sprinkler protected
4. City block bounded on 2 sides
5. Egress via atria (internal discharge)
6. Office occupants familiar with the building
7. Occupants alert and mobile
8. Return air via atrium (possibility of smoke/flame spread)
9. Separate occupancies and movement only via balcony – possible entrapment if fire b/w office and stair
10. Atrium – results in enhanced smoke production
11. Service shafts connecting all floors (smoke spread)
12.Occupants on ground floor may not be familiar
13.Visual access to atrium through glazed partitioning (fire cue, visibility etc.)
Part B (basically, in light with IFEG sections 1.2.3 and 1.2.4)
1. No description of type of structure
2. No description of people and characteristics (% of mobility impaired)
3. No mention of inter-relationships of the offices or possible layouts
4. No discussion of after hours
5. No description of fire systems to be installed or location
6. No mention of management systems such as EWIS, building alarm, floor wardens
Question 2
1. Non-compliance with DtS should be identified and clarified with BCA performance requirements.
2. Need more specific description of FRL for fire resistance
3. NO justification is given why two stairs can be used in lieu of three for evacuating.
4. NO information about exit door size, evacuation plan…
5. NO mention of evacuation strategy
6. Only beam detectors at the roof of atrium has been mentioned. What’s about other location (office, cafe)?
7. Need more specific description of using fire safety system like Fire hydrant, Fire extinguisher, Smoke Alarm…
8. Hazard analysis should have been conducted before suggesting trial designs.
Question 3
1. Performance clauses not given, only functional statements.
2. Functional statements are at guidance level, compliance level is performance requirement.
3. Non-compliance with DtS should have been identified and should be related back to the performance requirements.
4.Totally wrong interpretation of the BCA and the relationship between Objectives, Functional Statements, Performance Requirements and DTS.
Question 4
1. It is mentioned that design should be such that the occupants can avoid untenable conditions. A clear fire safety strategy of “every one out” should be stated.
2. The approach is - whether quantitative/qualitative, comparative/absolute, deterministic/probabilistic - not mentioned
3. Should explain Acceptance Criteria clearly - whether ASET vs RSET or ERL, etc.
4. Sensitivity / redundancy / factor of safety is not proposed
5. No information about Purser and Bryan
6. No mention of Fire Brigade Personnel Tenability Criteria
Question 5
1. Inadequate design fires and locations. No justification of 5MW or relation back to fuel load configuration, e.g. horizontal spread.
2. “In the offices, the fire will not be analysed since the office part of the building is not being dealt with by performance methods.” - unacceptable logic.
3. Ignores fire in offices and spill plumes and fires located closer to higher level floors.
4. No mention of sprinkler effectiveness.
5. No sprinkler failure scenarios or basis for accepting only sprinklered solution.
6. Relates smoke properties to fuel which is good
7. No information on Tewarson.
Question 6
1. Design fires and scenarios incomplete and confused
2. No information on QUICKFIRE (CFD or zone model) and its capability
3. Does not mention time to untenable conditions
4. No equation for optical density and CO concentration is given
5. No consideration of possible smoke movement into non-pressurised stairs
Question 7
1. Considers fire spread from atrium to offices not other way. What is likelihood of fire in offices and the associated fire sizes? Glass temp will not reach 240oC not shown.
2. Office fire may result in a larger fire due to radiation feedback.
3. No justification of 6m diameter. Should relate 5MW back to HRR/area or other basis.
4. Agree with external flame spread scenario via external vs internal. However, windows breaking may lead to very large fire, lead to breaking tempered glass separating atrium/office
Question 8
1. Good justification of why not using IFEG
2. Ignores evacuation through atrium even though people have to travel through atrium
3. Does not consider possible entrapment of one office part on a level
4. 6.5 minute response and coping time appears large
5. No calculation provided to show beam detector activation occurs 1 minute after the fire has started
6. Assumes both stairs are available
7. No information on Pauls.
8. No mention of training on EWIS
9. Has ignored people in café
10. No account taken of possible visitors / disabled persons
11. Is 10.5 min enough to avoid untenable condition? Only up to 5 min calculation is shown in Table 9.1
Question 9
1. Design fire not developed logically – including the size and locations
2. Sensitivity analysis
3. Not clear approach, method of analysis and acceptance criteria
4. Evacuation time is 10.5 min, tenability is shown up to 5 min.
5. Inadequate justification of model used/ inadequate referencing
6. Performance requirements to be set out.
7. Overall fire-safety strategy needs to be explained, i.e. how are the performance requirements to be met.
8. Many more….