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Query [19 Nov 2019]
HTM 05-02:2015 Section 6; External Fire Spread, makes no reference to the need for insulation incorporated into an external wall construction to be of limited combustibility. This appears to be a very deliberate omission as the performance of insulation is addressed in other standard guidance documents such as Approved Document B..

Is there any reason why HTM05-02 excludes any reference to the performance of insulation where the top floor of a hospital is set at more than 18m above the lowest adjacent Ground level?

Response
I’m certainly not aware of any deliberate intention to omit requirements regarding external wall construction from HTM 05-02. The reality is more likely that when the latest revision of HTM 05-02 (2014/2015) was drafted no-one fully considered the need for guidance requiring materials of limited combustiblity because it hadn’t been included in the previous edition or HTM 81 which preceded that.

Since the tragedy of Grenfell Tower there has been a greater focus on the materials used in external wall construction, but the powers that be are strangely reluctant to issue specific healthcare guidance, instead relying upon the guidance produced by MHCLG.

In my opinion (one which I’ve voiced to NHSI repeatedly since 2017 and which I note the FPA is voicing in its recent press release following last Friday’s fire in Bolton Cube) is that the building height is largely irrelevant, particularly in the context of a healthcare building. The potential for fire spread via combustible materials forming the external walls of the building presents an opportunity for a fire to spread across compartment boundaries, and particularly across building floors. Since in healthcare buildings there is a likelihood of occupants requiring assistance to evacuate, a fire across multiple compartments is likely to quickly escalate beyond the resources available to execute the evacuation plan. Hence, my advice to NHSI and the NHS Fire Working Group has been that the MHCLG restriction on materials used in the external wall construction etc. that applies to High Risk Residential buildings in excess of 18m should be applied to all healthcare buildings irrespective of building height..

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Query
The majority of the content written within Firecode is derived from documents such Approved Document B and various British Standard publications, I understand the need for such documents and the purpose for simplifying the application of fire safety within hospitals, however it becomes somewhat a restriction for the Fire Risk Assessor doing their jobs.

The local Authorities appear to be using Firecode as their bible when conducting external audits within hospitals and don't apply much flexibility. The following would be an example:

A section/department within a hospital is fitted with a certified L2 fire alarm system, AFD coverage of hazard rooms and escape routes accordingly. The category profile within the building is low risk (outpatients) no sleeping and occupied during day time hours only. Now considering all passive, active and managerial fire provisions are adequate, An L2 fire alarm system in these circumstances should be more than acceptable. However action from a recent audit has suggesting that because this same department is indirectly attached to a building that has sleeping risk i.e. down the street behind a number of 1 hr fire breaks then we should not deviate from L1.

Most Hospital designs are interconnected in one aspect or another, so should L1 be applied irrespective because of this, or can a Fire Risk Assessor actually assess risk and recommend a lower category of system given circumstances and justification?

Below is a section from HTM 05:03 Part B

"A Category L2 or L3 system should be provided for healthcare premises other than hospitals. A category L1 system should be provided throughout all parts of hospital premises."

It also states within this document that it should be read in conjunction with BS5839-1:2013 which within Section 2: Design considerations reads the following:

8.1.1 General

"The appropriate extent of automatic fire detection will normally be determined by a fire risk assessment, rather than a rigid application of system Category to every building of a specific type or occupancy."

The above passage from BS 5839 seems somewhat a sensible approach but can it be applied or should we L1 everything irrespectively IAW with Firecode.

Response
As the author of HTM 05-03 Part B, I concur with your view that if the fire risk assessment has identified that:

• There is no sleeping risk in the area in question;
• There is no risk of a fire in the area in question going undetected such that it may pose a risk to occupants of the area in question or those in the building beyond;
• That occupants of the area in question area able to raise the alarm and effect their escape in a timely manner; and
• Providing that in the event of any of the above changing a revision to the fire risk assessment and appropriate risk mitigation is undertaken,

There should be no reason to upgrade the fire detection provision in the area in question from L2 to L1.

Additionally, I would question the appropriateness of the fire service inspector effectively giving precedence to a guidance document, written in isolation of knowledge of the premises in question, rather than a competent assessment of the fire risks present.

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Query
The latest (2014) version of HTM 05-02 Table 7 requires air transfer grilles in fire hazard rooms to be provided with dampers activated by automatic fire detection, but appears to permit dampers in ductwork penetrating the fire hazard room to be thermally activated.

Why is there a difference?

Response
The short answer is I don't believe that there is a difference.

It doesn't appear to make sense that a transfer grille requires a damper activated by automatic detection, if all other dampers installed in ductwork penetrating the same structure are activated thermally. In the extreme, it would be possible to construct a fire hazard room with a transfer grille and a short length of larger area duct to the side of it. The damper in the transfer grille would require a damper operated by the automatic detection, whilst the larger opening adjacent would only require a thermally activated damper.

Whilst such a configuration is unlikely, this appears to present circumstances that would circumvent the requirement for transfer grilles to prevent the passage of smoke, by constructing a ducted arrangement in the place of the transfer grille and providing a thermally activated damper.

Since, as stated in HTM 05-02, hazard rooms perform the vital role of protecting escape routes from the effects of a fire, I would always recommend that hazard rooms should protect against the passage of smoke, and therefore should be provided with fire and smoke dampers activated by the automatic detection.

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Query
Are CT scanner rooms and MRI scanner rooms considered hazard rooms?

I have a customer building a new CT scanner room in very close proximity to an existing MRI scanner room, both will use a common control viewing room. A second MRI scanner is also located in close proximity within the same 1 hr fire compartment namely known as Imaging Dept.

We recommended the new scanner room be constructed to a 1 hour fire compartment providing fire separation from the other scanners in close proximity.

HTM05-02 appears not to give guidance on these rooms although their continued service and support to the medical team and hospital and high value replacement, we feel should be considered.

Please can you clarify this and together with your valued thoughts.

Response
Hazard rooms can be considered as locations where the contents or processes therein are considered to present a higher than usual potential for fire. CT scanner and MRI rooms are not considered fire hazard rooms, although some protection may be necessary to the control rooms where it is necessary for personnel to remain whilst the equipment is safely de-energised.

I agree that some consideration should be given to the importance of the high value equipment and its importance to service continuity. Whether each room should form a protected enclosure, or whether rooms should be grouped such that multiple scanners of the same type are separated thus ensuring that a single fire shouldn't prevent CT scanning or MRI scanning services in their entirety, depends upon a number of factors including:

• The arrangement of rooms and equipment;
• The cost of providing extensive compartmentation including fire stopping, ventilation duct dampers etc.
• The separation of electrical supplies, ventilation and other building services necessary to continue the operation of protected equipment;
• The availability of alternative imaging services.

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Query
HTM 05-03 part B allows that detection need not normally be provided in voids provided certain conditions are met, and subject to a risk assessment.

If the criteria for not installing detection above a false ceiling are fulfilled does this void (above a false ceiling) fall within the definition of void in the HTM?

Response
The simple answer to your query is yes. HTM 05-03 Part B refers to voids of any depth and the criteria for the omission of fire detection from voids is equally applicable to ceiling voids, floor voids and roof voids.

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Query
I wonder if you would be prepared to confirm whether or not the reference to demountable ceilings in HTM 05 02 when commenting on the use of fire resisting ceilings to fire hazard rooms simply means lay in grid suspended ceilings.

Also, to your knowledge, has reliance ever been placed on the fire resistance (actual or assumed) of lay in grid suspended ceilings in hospitals?

Response
The reference to demountable ceilings in HTM 05-02 refers to any type of ceiling that has removable elements including lay in grid, clipped metal pan etc.

Whilst it is possible to construct a lay in grid suspended ceiling to achieve a fire rating, in the majority of hospital environments it is unlikely that the fire integrity of the ceiling would remain intact throughout the life of the ceiling. In particular, the clips required to secure the ceiling tiles in place within the grid will need to be removed for access to services and are notoriously difficult to re-secure. In all likelihood the clips will not be reinstalled thereby detracting from the fire integrity of the ceiling. Another thing to bear in mind is that it is not usual for a suspended ceiling to form part of the fire enclosure, hence should this be proposed there needs to be realistic management controls to ensure that the fire integrity of the ceiling is maintained particularly where services penetrate the ceiling or equipment is fixed to the ceiling.

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Query
I am surveying existing hospitals, to see if they comply with the required fire strategy. There are many doors which have a coloured/multi-coloured circular plug in the leading edge of the door leafs, which I need to identify.

How can I do this, is there a standard chart?

Response
There is a standard colour chart for the plastic core plugs. The current scheme for marking fire doors is part of the BM TRADA Q-Mark and uses coloured core plugs where the outer colour of the plug represents the fire rating of the door, and the inner coloured tree indicates how the door was supplied e.g whether or not seals or glazing was factory fitted. Details here

Incidentally, Firecode recommends that each fire door leaf is fitted with an identification disc at least 45mm in diameter and clearly indicating the fire-resisting standard of the door. [HTM05-02, Appendix B, Section B5].

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Query
I'm dealing with a 30 bed ITU department with no sub-division (the ancillary areas are in a separate sub-compartment but beds are in the same sub-compartment). I have concerns about this. Given the time taken to evacuate 30 high dependency patients from the ward area (I have been working on a detailed fire response procedure for the department), the potential for fire spread during that period is considerable - I can't imagine that it could be carried out safely in the safe egress time available. The ward is on an upper floor, so all evacuation is internal.

The building is only three or four years old and the general layout does not really meet the compartmentation and sub-compartmentation descriptions of the HTM. I suppose that it could be argued that it does, but it misses the point somewhat. The general building layout adds to my concerns.

Do you have an opinion on the largest number of ITU patients that could, or should, be safely accommodated in a single sub-compartment? (The HTM seems to imply that up to 30 would be acceptable - although my approach is to include realistic evacuation scenarios in order to limit the number of beds further.)

Are you aware of any hospital ward fire growth rates that I could use to model the situation?

Response
It's correct that Firecode says nothing about the maximum number of ITU patients that can be accommodated in the same sub-compartment other than the general 30 patient limit which applies anywhere. However, the design of any ITU should ensue that the majority of hazard rooms are located in a separate sub-compartment. The reality is that there are thankfully very few fires that occur within the ITU department which in turn means that an ITU presents a lower risk than a general medical ward. In addition, the staff to patient ratios within ITU are usually 1:1 which is significantly better than the 1:15 in a general ward.

Of course, the flip side is that the patients are seriously ill and evacuating the ITU will always be time consuming, require a large number of staff and take a considerable time to achieve. Generally speaking, when ITU patients are moved for treatment elsewhere in the hospital in a non-emergency situation, the preparation to move a patient with life-support is of the order of 20 minutes and requires two members of staff. In an emergency situation I'm sure that time would be significantly reduced.

It is worth remembering that an evacuation of ITU is a last resort, and in many cases patients would be better off staying put. Generally, if the fire is not in the ITU department patients have successfully remained in situ whilst attending staff have evacuated with those patients that are not on ventilators. Those patients that are on ventilators are unlikely to be affected by any smoke that may enter the department so staff set their beds to the lowest height (to minimise their exposure to the smoke layer) and ensure that any medication such as drips, syringe pumps etc. aren't about to run out before they evacuate away from the smoke leaving the ventilated patients behind.

Despite all of the above, you may still feel that should a fire occur within the ITU, the evacuation of patients is too much to expect (even given that it may be life-threatening to move some patients so staff may determine that it is safer for them to remain in situ) in which case you will need to explore ways of separating the ITU patient area further. In my experience you are likely to meet with some opposition since the nursing and clinical staff usually want an open patient area for operational issues. (It's easier to move patients in a hurry, it's easier to get the crash team and other medical teams to a patient in a hurry etc.)

As for fire growth data, there's no sufficiently detailed, published data that I'm aware of. Despite numerous requests the Department of Health didn't fund the fire performance research that I requested whilst I headed the DH fire team. I'd suggest a reasonable basis for modelling would be a slow to medium growth rate since the majority of combustible items will be combustion modified or fire retardant treated, although some of the fire retardancy will degrade over time, and it doesn't take much (3-4 sheets of newspaper) to overcome the fire retardancy on items such as bed curtains. Even then, the model won't take account of the oxygen enriched fires we get when a patient takes an oxygen mask off and leaves it on the bed whilst it's still delivering oxygen; however, this is unlikely to occur in an ITU.

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Query
In our Women's Hospital we are planning to install electro-magnetic locks for selected doors to prevent child abduction. The new proposal requires interfacing with Fire Alarm System. I would like your advice on how feasible it would be and the complications involved.

Response
Fitting electro-magnetic locks to doors on fire escape routes is not uncommon. There are various reasons why this should be done, including the prevention of child abduction. The biggest issue to overcome is the obvious locking of doors on fire escape routes which will prevent immediate escape in the event of a fire. Linking the electro-magnetic locks to the automatic fire detection system by means of an interface will usually provide a control to unlock the doors when a fire is detected, however, this raises other issues:

1. If the automatic detection and alarm system operates to release the door locks, what stops a person wishing to abduct a child operating a manual call point to unlock the doors?

   To overcome this potential problem, as a minimum, manual call points could be installed some distance (3-5m) back from the locked door such that anyone attempting to abduct a child would have to re-trace their steps once they had reached the locked door, in the event of a fire where the automatic detection has not activated the alarm, staff would understand that the manual call point would need activation and could operate it on their way to the exit.

   Perhaps a better solution, if the layout of the building permits it, is to unlock the electro-magnetic locks that provide escape from the area in which a fire is detected, this would allow escape into an adjacent compartment or secure external compound. Further escape would not be possible unless the fire spreads to the adjoining compartment, or staff manually initiate further escape which provides an opportunity for the staff to verify that no child is being abducted.

2. The interface arrangement is unlikely to be truly fail-safe i.e. the interface control relay will not be permanently energised, hence if the relay were not to receive a control signal to switch, if the power to the relay were to fail or the relay contacts were to fail to operate, the electro-magnetic locks could remain locked despite the activation of the fire alarm system.

   To overcome this potential problem, British Standard 7273 Part 4:2007 recommends the provision of manual override controls (green break-glass) that directly interrupt the power to the electro-magnetic lock when activated. This approach can significantly undermine security, although a similar approach may be taken as for manual call points by installing them some distance (3-5m) back from the locked door.

   Alternatively, on the basis of risk assessment and the assurance of well trained staff with the means to over-ride the locking mechanism by means of a keyswitch or similar device which interrupts the power to the electro-magnetic lock, it may be reasonable to omit the manual release (green break-glass) controls.

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Query
Our organisation is planning to convert a newly added building as a Cardiac Hospital. According to the local regulation in Qatar, a sprinkler installation has been provided through out the building. But three rooms in this building will be converted to an Operation Theatre. Is it feasible to keep the sprinkler system in the Planned Operation Theatre area or is there any alternative Fire Protection Installation.

Response
From a fire safety perspective it is possible to retain sprinklers in operating theatres since they should only operate if local conditions within the theatre are life threatening. However, the use of pendant sprinkler fittings in operating theatres presents other operational issues such as infection control since the structure of the sprinkler head will allow dust and other contamination to collect. Cleaning and decontaminating sprinkler heads won't be easy and could lead to a risk of accidental activation. This may be overcome to a large extent by the use of recessed sprinkler heads concealed behind a ceiling plate.

Testing and maintenance of the sprinkler heads in the theatres may also prove difficult. Personally I'd risk assess the need for sprinklers in the operating theatre rooms. Generally the fire loads in operating theatres are comparatively low and the relatively high staff presence reduces the risk even further. In the U.K. our fire incident records indicate that fires in operating theatres are very rare and are usually quickly dealt with by the staff that are present. Our main areas of fire incidents within the operating theatre department are the disposal rooms. It is possible that swabs and drapes that have become contaminated with surgical spirit or other flammable contaminants self ignite when compressed in the disposal bins.

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Query
I am having difficulties with older hospitals where there is only one fire door to the stairway; I am tempted to recommend lobby protection to the stairway and 30 minutes fire doors, which goes a long way to meeting the HTM 05 02 approach, although a single 60 minute door may be the only option in many cases. Is a single 60 minute fire door acceptable?

Response
In addition to the fire rating of the fire doors you should consider the smoke stopping potential of a protected lobby as opposed to a single door. If you're trying to escape from a fire through a single door into a protected stair you could reasonably expect some smoke from the fire to be entering the stair with you. Even if you're not evacuating using that particular stair, protecting the stair from smoke will rely upon the fire doors and seals between the fire and the stair. Knowing the abuse that fire doors suffer in hospitals, relying on a single door seal to prevent smoke filling a protected stair doesn't seem like a sound idea especially if there aren't many stairs to begin with!

If at all possible I'd recommend constructing a protected lobby.

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Query
I am interested in your opinion on the fire resistance of fire doors to stairways. In many hospitals I see staircases provided only with 30 minute doors, yet section 6 of HTM 05 02 suggests that protected shafts should be provided with the same fire resistance as the element throughout.

Certainly, it has been common in the past (Building Regulations guidance) to allow doors to protected shafts to have only half the fire resistance of the shaft. What is your interpretation of the HTM, and what do you think is the most appropriate protection?

Response
The rating of fire doors to protected stairs should be 30 minutes (FD30S) where accessed from a hospital street or both doors of the protected lobby approach to protected stairs should be rated to 30 minutes (FD30S). In older hospital buildings it is not uncommon to find an escape stairway accessed from a corridor, which does not form a hospital street, without a protected lobby. In such circumstances the actual fire rating of the access door is important as are the smoke stop capabilities. The presence of a stair effectively breaches the compartment floors (60 minutes rated), by providing 30 minute doors at each level one could argue that the 60 minute compartmentation has been preserved. However, this only holds true for a stair that passes between two levels (e.g. ground to first floor). Where a stair provided with 30 minute doors extends beyond two floors, its presence potentially reduces the level of compartmentation.

Consider a stair that extends from ground floor, through first floor to a second floor. If the enclosure to the stair is provided with a single 30 minute fire door at each level, a fire in the ground floor level accommodation will theoretically take 30 minutes to enter the stairway. From there it will spread upwards reaching the second floor where theoretically it will burn through the fire door to reach the second floor accommodation in another 30 minutes i.e. total time for a fire in the ground floor accommodation to reach the second floor accommodation approx. 60 minutes. Since this is less than the the total fire rating provided by the two compartment floors that separate the second floor accommodation from the ground floor accommodation, the level of compartmentation has been compromised.

If the stairway has been provided with protected lobbies, each fitted with two 30 minute fire doors, a fire in the ground floor level accommodation will theoretically take 30 minutes to enter the protected lobby and theoretically a further 30 minutes to enter the stairway. From there it will spread upwards reaching the second floor where theoretically it will burn through the fire door to reach the second floor lobby in another 30 minutes and take a further 30 minutes to enter the second floor accommodation i.e. total time for a fire in the ground floor accommodation to reach the second floor accommodation approx. 120 minutes. This is the same time as the total fire rating provided by the two compartment floors that separate the second floor accommodation from the ground floor accommodation. Hence the compartmentation is preserved.

The argument above doesn't hold true for stairs that extend beyond the second floor, but the provision of protected lobbies theoretically affords 60 minutes separation between any accommodation and the protected stair. If this is breached, the automatic detection within the stair should be activated and the cause & effects of the fire detection and alarm system should sound an intermittent alarm in the accommodation at each level adjacent to the affected stair. At this point the fire within the stair is theoretically 60 minutes away from the accommodation adjacent to the stair and staff will have been alerted to its presence.

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Query
I understand The Department of Health has undertaken a detailed review of the NHS Firecode. This has led to some dramatic changes being made to the existing documents, which will be replaced by three key pieces of guidance. The changes will be implemented next year in line with the Regulatory Reform (Fire Safety) Order. Could you explain what these changes will involve?

Response
Having checked with the Department of Health (13-5-10) I can confirm that no such review of Firecode has taken place and that the last Firecode review pre-dates the transition to the HTM 05 series of guidance.

Currently the only revision to Firecode taking place is the imminent publication of HTM05-03 Part M.

I understand that your query initiated from information contained in marketing material from BRE regarding their "Fire Safety Design Course for Hospitals", I can only assume that BRE has used a previous course description by mistake.

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Query
HTM05-02 clause 6.35 and fig 10 point us towards the defunct BS5588-9 for the actuation of fire dampers. However, the successor to 5588, BS 9999-2008 states that it does not cover occupancy characteristic D. Do we follow the guidance for occupancy characteristics Cii & Ciii?

Also HTM05-02 fig 10 seems to give us a choice of following the HTM or the BS. For occupancy characteristic Cii & Ciii the BS points to smoke detection either side of the compartment wall whereas the HTM just states "by the operation of the alarm detection system in the compartments either side of the compartment wall"?

Response
This issue is a symptom of the update cycle for Firecode not coinciding with that of the British Standards. This is also highlighted by the references to BS5588 Part 7 for atria, and whilst the new HTM 05-03 Part M is imminent, HTM 05-02 will still refer to BS5588 Part 7 until an update is published. Using the guidance for occupancy characteristics Cii & Ciii of BS9999-2008 would be sensible in this instance.

There is a difference in the recommendations of the HTM and that of the British Standard in that the HTM recommends the use of dampers activated by automatic smoke detection wherever ductwork passes through compartmentation and thermally activated dampers in sub-compartment walls whilst BS9999 refers to dampers activated by automatic smoke detection wherever ductwork passes through fire resisting construction.

Since HTM 05-02 refers to HTM 05-03 Part B which details automatic detection to L1 category, in essence the HTM reflects the same philosophy as the British Standard.

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Query
HTM 05-02 Paragraph 5.86:- recommends the sub-compartmentation of theatre suites so that no more than 50% of operating theatres would be compromised at any one time in the event of a fire. Is this condition designed more for safety in fire or property protection so that not all of the theatres might be damaged by the same fire?

Response
The recommendation for sub-compartmentation is intended to achieve two objectives.

Firstly it allows a degree of flexibility should the operating department be involved in fire in that it may allow a theatre team that is forced to evacuate during a procedure to relocate to a theatre in a separate sub-compartment where they may conclude or otherwise safely abort the procedure.

Secondly, the provision of sub-compartmentation within the operating department may limit the spread of fire sufficiently to allow the unaffected theatres to quickly be brought back into service once the fire incident has been dealt with.

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Query
HTM 05-02 Paragraph 5.52:- In hospitals not provided with hospital streets, stairways should be provided to each compartment. Does this mean that there should be a staircase in each compartment?

Response
Each compartment above ground level not provided access to a hospital street should be provided access to a protected stair. This doesn't necessarily mean that each compartment must have a staircase. A stair may be accessed by more than one adjacent compartment. However, such an arrangement needs to be carefully planned to ensure that the lobby to the protected stair doesn't form a through route, and that the compartment exits are maintained as alternatives i.e. the exit to the protected stair and the exit to the adjacent compartment are sufficiently separated so as to be considered alternative.

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Query
HTM 05-02 Paragraph 5.29 and other paragraphs:- the area of acceptable glazing is expressed as 1000 mm2. I assume that this means an area of 1 metre by 1 metre.

Response
Your assumption is correct, someone (and no one is admitting to it) cocked up and decided that the revised HTMs would use mm as the base unit for measurements of less than 5m. It follows then that mm2 would be used for smaller areas rather than m2. However, whilst the person that attempted the conversion understood that there are 1000mm in 1m, they failed dismally when it came to area measurements and incorrectly assumed that there must be 1000mm2 in 1m2. This incorrect conversion has been repeated throughout HTM 05-02 with some really daft outcomes such as:

Paragraph 6.24 b - a permanent opening for each lift of 100mm2 (1cm2) instead of the 0.1m2 detailed in previous guidance or:

Table 4 - where small rooms are described as a maximum or 4000mm2 (0.004m2) instead of the 4m2 detailed in previous guidance

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Query
Appendix B of HTM 05-03 Part H includes two performance grading charts. When we measure our performance on the Figure A1 chart (extrapolated for the number of detector and call points on our system) our performance is in Grade A, but when measured against the Figure A2 chart our performance is level 3.

Why is it that an apparently good performance indicated by Figure A1 is classed as a poor performance indicated by Figure A2?

Response
The apparent discrepancy in performance derives from two issues. The first is that the two figures relate to different criteria. Figure A1 relates to False Alarms whilst Figure A2 relates to Unwanted Fire Signals (i.e. false alarms that have been communicated to the fire service as fire incidents).

Secondly, Figure A1 relates to the performance grading described in paragraph 1.17 of the guidance which refers to a linear ratio thus allowing extrapolation beyond the criteria shown in the figure. However, Figure A2 is replicated from the CFOA policy for the reduction of false alarms and unwanted fire signals and as such there is a point at which the level of unwanted signals relating to a specific performance is considered independent to the number of detectors and call points present on the system.

For large systems. such as those found in most hospitals, the number of detectors and call points present is usually way above the maximum number indicated in the CFOA chart hence it is not unusual to find that hospitals don't meet Performance Level 1 in the CFOA policy.

Whilst in theory performance below Level 1 could result in a reduced fire service attendance to an unconfirmed alarm call, the transition between performance levels does not automatically trigger a reduced fire service response. A transition between performance levels acts as a trigger for the fire service to review their automatic attendance levels and such a review should involve discussions with the Trust.

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Query
Section 5.14 of HTM 81 required that where three or more compartments are required, the exits from each compartment should be located so that there are at least two alternative exits which provide horizontal escape to adjoining but separate compartments.

This section has been revised in HTM 05 02 where this requirement appears to be gone? Is this correct and if so why is this?

Response
The guidance you refer to that was in paragraph 5.14 of HTM 81 is still present in HTM 05-02 albeit in a slightly different format.

HTM 05-02 incorporates details in respect of the number of compartment exits and how they are to provide communication between compartments in paragraphs 5.7 and 5.9 which refer to a minimum number of compartments per storey and the minimum number of exits that should be provided from each compartment. Each of these paragraphs also states that each compartment should be interconnecting i.e. it should be possible to reach each compartment on the storey from any starting position on that storey by travelling through an adjacent compartment or series of compartments.

Paragraph 5.16 of HTM 05-02 contains guidance in respect of alternative exits. The wording has changed to clarify the recommendation regarding the location of alternative exits. The guidance of HTM 81 paragraph 5.14 could be construed to mean that each compartment required two alternative exits i.e. in a compartment with 3 exits only two exits need be located sufficiently remote from each other as to be considered alternative. The guidance of HTM05-02 goes further in stating that:

"in the event of one exit becoming unavailable, any alternative exits should be sufficiently remote from each other to ensure availability".

Whilst I'd agree that this may appear a little ambiguous, the intention is that for a compartment with 3 exits, and an event which renders one exit unavailable, two compartment exits should still be available.

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Query
As the author of HTM 05-03 Part B: Fire detection and alarm systems could you give me some advice please? On two PFI projects - with the same building control officer (BCO) and Fire Officer - all the manual call points (MCPs) at final exits from stairway enclosures have been deleted from the scheme. I have always considered that all final exits - other than those into an enclosed courtyard - should have an MCP by virtue of BS 5839, and the alarm company for these two schemes happens to agree. The MCPs were deleted from the alarm company proposals on the advice of / or with the agreement of (I'm not sure which) the BCO and Fire Brigade. The Fire Officer is citing paragraph 5.6 b of HTM 82, which appears in your document as 5.7 b. I don't believe that this paragraph is saying that an MCP is not required at the final exit at the bottom (landing) of a stairway. Can you please clarify?

Response
Paragraph 5.7b was included to clarify the recommendations of BS5839 Part 1 in respect of the location of manual call points in and around stairs. The latest edition of the British Standard (2002+A2:2008) provides details under paragraph 20.2c which indicate that manual call points should be located at each storey exit and they may be sited within the accommodation or on the landing of a stairway to which the storey exit gives access. HTM05-03 Part B paragraph 5.7b clarifies the Firecode recommendations in this respect by recommending that manual call points are located on the accommodation side of each storey exit to a stair in preference to the stairway landing. However, BS5839 Part 1 paragraph 20.2c continues its recommendations with:

"In multi-storey buildings with phased evacuation, in which only a limited number of floors are evacuated at one time, only the former option applies; under these circumstances, manual call points should not be located on stairway landings, as persons travelling down the stairway might operate a manual call point several floors below that on which a fire is located, resulting in evacuation of inappropriate areas."

Whilst this recommendation specifically addresses the issue of manual call points on stairway landings, the same point could be made where a manual call point is located at the final exit from the stair. i.e. someone exiting from an upper floor may activate the call point at the foot of the stair. Since the stair will form its own alarm zone, upon activation of the final exit call point the stair zone would sound a continuous alarm, the result would be that the accommodation adjacent to the stair at all levels would sound intermittently. Whilst the alarm system can be programmed not to sound an intermittent alarm in the accommodation adjacent to the stair when the call point at the final exit is actuated, I'd question what practical use a continuous alarm in the stair would be. I guess I'm really agreeing with the BCO & fire officer, although not for the reasons they've cited.

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Query
HTM 05-02 para 5.9 requires each compartment on floors above 12m to have a minimum area of 500m2 unless it is a hospital street. Para 5.10 allows the compartment size to be reduced to 350m2 where sprinklers are installed. Why is there a minimum compartment size specified and why does installing sprinklers mean that compartment sizes can be reduced? Usually compartment sizes can be increased when sprinklers are provided.

Response
The restriction placed upon the minimum area of a compartment for floors over 12m above ground is intended to prevent tall and small footprint buildings. Where the footprint of the building is constrained there is less opportunity to take refuge remote from any fire which may potentially increase the likelihood that vertical escape will be necessary. The installation of sprinklers should limit the size of a fire thus reducing its potential impact and the likelihood that vertical escape will be necessary. As a result the guidance accepts smaller compartment sizes.

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Query
Our fire alarm provider is insisting that the commissioning certificate for our fire alarm system records a variation because the alarm zones are configured by compartment rather than by sub-compartment as described in HTM 05-03B. The previous alarm system operated on a compartment by compartment basis so it hasn't changed. Should the commisioning certificate include a variation and if so why is it different to the system we had before we replaced it?

Response
Strictly the commissioning certificate should include a variation to HTM 05-03 Part B since the guidance does recommend that alarm zones coincide with sub-compartments. The guidance in HTM 82 was the same so strictly speaking your previous system should have been subject to the same variation on the commissioning certificate. There was always a conflict with HTM 82 in that whilst it recommended that the alarm zones coincided with sub-compartments, the process of progressive horizontal evacuation supported by the guidance of then HTM 81 was on a compartment by compartment basis. This is borne out by the recommendations to provide ductwork penetrating compartment boundaries with smoke dampers whilst sub-compartment boundaries are fitted with thermally activated fire dampers. What's muddied the waters even more is that when HTM 82 was updated to become HTM 05-03 Part B, it was drafted prior to HTM 05-02 and the fire team at the Department of Health had intended to change the guidance on dampers to require smoke dampers at both compartment and sub-compartment boundaries, hence, HTM 05-03 Part B contained the same recommendations in respect of alarm zones as HTM 82. Subsequent to HTM 05-02 Part B being published the fire team at the Department of Health had a change of heart regarding dampers and continued with the recommendations of HTM 81. As a result, there remains a conflict between the alarm zones in the fire detection and alarm guidance and the physical measures to support PHE in HTM 05-02. Hopefully this will be addressed when HTM 05-03 Part B is refreshed.

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Query
Is it possible to make use of our passenger lifts to evacuate patients from upper floors?

Response
The use of lifts for fire evacuation is certainly possible and HTM 05-03 Part E provides guidance for Escape Bed Lifts. However, since you refer to "passenger lifts" it appears that you do not have escape bed lifts. The use of standard lifts for fire evacuation is generally not accepted, however, with sufficient assessment of the potential risks a case for their use may be made. Factors such as the remoteness of the lift provisions from a fire, the protection of power supply cables, standby generators, availability of staff to rescue persons trapped in a lift, robust communication systems to co-ordinate the evacuation, detailed evacuation planning and co-ordination with fire service access and fire fighting activity can help to build a case for the use of standard lifts for evacuation.

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