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BCC Ruling No. 00-22-754

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BUILDING CODE COMMISSION DECISION ON B.C.C. No. 00-22-754

IN THE MATTER OF Subsection 24 (1) of the Building Code Act, 1992. AND IN

THE MATTER OF Article Article 3.2.8.9 and Sentence 3.2.8.4.(4) of Regulation 403, as amended by O. Reg. 22/98, 102/98, 122/98, 152/99, 278/99, 593/99, 597/99 and 205/00 (the "Ontario Building Code").

AND IN THE MATTER OF an application by Mr. Greg Varrette, Project Co-ordinator, Thomas Fuller Construction Co. Ltd., 2700 Queensview Drive, Ottawa, Ontario for the resolution of a dispute with Ms. Terry Dalkowski, Chief Building Official, City of Nepean, to determine whether the 45 m travel distances in the existing portions of the building, which are not to be protected by a 2 hour rated wall at the proposed atrium, provide sufficiency of compliance with Sentence 3.2.8.4.(4) of the Ontario Building Code (OBC), and whether the proposed smoke management system designed in conformance with NFPA 92B, "Guide to Smoke Management in Malls, Atria and Large Areas", and intended for the atrium to be constructed adjoining to the existing building, provides sufficiency of compliance with Article 3.2.8.9. of the OBC, at JDS Uniphase, 3000 Merivale Road, Nepean, Ontario.

APPLICANT
Mr. Greg Varrette, Project Co-ordinator
Thomas Fuller Construction Co. Ltd.
Ottawa, Ontario

RESPONDENT
Ms. Terry Dalkowski
Chief Building Official
City of Nepean

PANEL
Dr. Kenneth Peaker, Chair-Designate
Mr. John Guthrie
Mr. Fred Barkhouse

PLACE
Toronto and Ottawa, Ontario

DATE OF HEARING

May 18th, 2000

DATE OF RULING
May 18th, 2000

APPEARANCES

Mr. Jonathan Rubes, Leber/Rubes Inc.
Toronto, Ontario
Agent for the Applicant

Mr. Frank Bidin
City of Nepean
Designate for the Respondent

RULING

1. The Applicant

Mr. Greg Varrette, Project Co-ordinator, Thomas Fuller Construction Co. Ltd., Ottawa, Ontario, has applied for a building permit under the Building Code Act, 1992 to construct a new addition consisting of an office structure and a large atrium onto an existing office-industrial complex known as JDS Uniphase, at 3000 Merivale Road, Nepean, Ontario.

2. Description of Construction

The Applicant is proposing to construct a three storey office structure and multi-storey atrium onto an existing four storey office-industrial complex that serves as the corporate world headquarters for JDS Uniphase, a producer of fibre optic components. The existing building, which initially commenced construction in 1998, has been built in three phases. Phases 1 and 2 are both four storey office-industrial areas that combine administration and manufacturing within each. Located to the south-east of phases 1 and 2 is phase 3, which is currently under construction. It too is a four storey office-industrial area. The proposed construction is designated as phase 4 and, as office space only, will be used exclusively for administration purposes. Also proposed is an atrium to be located in the centre of all four phases that will effectively join these areas together to form a new, larger building. (The phases of the existing building were previously connected by common service and office areas and walkways.)

The existing complex, phases 1 to 3, is currently classified as having Group D (business) and Group F - Division 3 (low hazard industrial) major occupancies. The completed building, with the proposed addition, will have the same classifications. Including phase 4, the total building area for the entire structure will be 21,000 m2 and the building height will be four storeys. The building is, and will be, of noncombustible construction and is to be fully sprinklered with a supervised and monitored system and equipped with a standpipe and hose and fire alarm systems throughout.

A smaller, full height atrium, known as the Executive Atrium, is also proposed to be included within the new phase 4 administration building. This atrium will fully comply with OBC requirements for interconnected floor spaces in Subsection 3.2.8. and will feature "the provision of smoke detectors and baffles at floor openings, limited travel distance, and exhaust at a rate of 6 air changes per hour from the top of the atrium." This atrium is not in dispute.

The proposed construction of the large atrium space, however, has implications for the existing building. Construction of the atrium facility (the opening of which complies with the minimum size requirements for openings in floor assemblies found in Article 3.2.8.3. of the OBC) means that some of the existing exterior curtain walls in the phase 1, 2 and 3 three portions will become interior walls adjoining the atrium space. As these walls are comprised mostly of fixed laminated glass panels, they are considered unrated assemblies and will act as smoke separations only. Without a continuous and rated fire separation between the atrium and the existing areas, the floor levels of the office and manufacturing portions will thus become interconnected floor space with the atrium. This creation of an interconnected floor space situation raises two main areas of dispute.

The first deals with the travel distances in the existing building. The travel distances in these areas of the sprinklered building have been designed and built to meet the OBC requirements for Group D and F3 occupancies for a floor space not considered to be interconnected, which in this case is 45 m for both. (Clause 3.4.2.5.(1)(c) permits the travel distances to be increased to 45 m in a sprinklered building of these occupancies, however, Sentence 3.2.8.4.(4) waives this increased travel distance.) The Applicant is proposing that these existing travel distances, even though they are now in an interconnected floor space, remain unchanged. The only modification intended for the existing portions of the building is decommissioning of certain stairwells that will no longer discharge to the exterior due to the pending construction of the central atrium. It is proposed that the decommissioned stairs will act as communication and circulation facilities. (It should be noted that the phase 4 administration building will be built to comply with the interconnected floor space requirements of OBC Subsections 3.2.8., including the maximum travel distance of 40 m permitted in Sentence 3.2.8.4.(4) for a Group D occupancy in a sprinklered building on an floor area in an interconnected space.)

The second area of dispute raised by the construction of the proposed atrium concerns the smoke management within the interconnected floor space area. This dispute specifically relates to the existing phases 1 to 3 and the large atrium. (Whereas the phase 4 area is considered to be within the larger interconnected floor space with respect to the central atrium, this phase has been designed to meet the requirements for interconnected floor space as mandated in Subsection 3.2.8. of the OBC. Therefore, as new construction, phase 4 will be equipped with a zoned smoke management system as per Article 3.2.8.9.) Due to the construction difficulties involved in retrofitting the existing building's HVAC system, and because of the sheer volume of air space in the proposed large atrium, the Applicant is intending to offer an alternative smoke management system than that required by Code for the interconnected floor space area. The major features of this smoke management system, as described by the Applicant, are as follows:

- "smoke exhaust from the top of the atrium at a rate as specified by NFPA 92B"; (The exhaust rate for the atrium area only, as proposed, is 224 489 m3/hour which is approximately four air changes per hour for that 56,633 m3 space.)

- "no zoned smoke exhaust for existing floor areas which are smoke separated from the atrium"; and,

- "automatic and manual operation of all fans and controls associated with atrium exhaust. Manual activation capability of supply fans serving existing floor areas at 100% outdoor air, so as to provide positive pressure of a floor area in the even (sic) that a fire within the atrium causes glazing to break."

To achieve compliance with the Code with respect to the above referenced items in dispute, the Applicant is offering the following package of safety features in the building:

- "existing exterior walls and glazing to remain in place to act as a smoke separation between the atrium and existing floor areas;

- "closely spaced pendant quick response sprinklers to be installed around the interior of the atrium at the level of the 2nd floor slab to respond to fires originating in the atrium in close proximity with the atrium walls; (and,)

- "smoke exhaust from the top of the atrium in accordance with the engineered design criteria of NFPA 92B."

(It should be noted that while the smoke management of the interconnected floor space is an issue at dispute, the Applicant is not simply offering the NFPA 92B system as an alternative to the Code's prescriptive smoke management requirements but also as a proposed measure to relieve the travel distance deficiency.)

The Applicant is also providing smoke detection in various parts of the building. Specifically, smoke detectors are to be installed within the second and third floor circulation spaces of the new administration building as well as at the top of the large atrium. These latter detectors are to operate the atrium's smoke management system. No detection is proposed to be installed on existing floor areas at the fixed glazing overlooking the atrium. This is because it is anticipated that the glazing will prevent smoke caused by a fire originating in the existing areas from entering into the atrium. (Except, of course, when a fire begins in the immediate vicinity of the glazing and breaks the glass separation. In this scenario, however, according to the Applicant the atrium smoke management and detection systems and the remainder of the glazing would perform as if the fire occurred within the atrium itself.)

3. Dispute

There are two disputes between the Applicant and the Respondent. The first is whether the 45 m travel distances in the existing portions of the building, which are not to be protected by a 2 hour rated wall at the proposed atrium, provide sufficiency of compliance with Sentence 3.2.8.4.(4) of the OBC. The second is whether the proposed smoke management system designed in conformance with NFPA 92B, "Guide to Smoke Management in Malls, Atria and Large Areas", and intended for the atrium to be constructed adjoining to the existing building, provides sufficiency of compliance with Article 3.2.8.9. of the OBC. (The aforementioned Code provisions are applicable to the existing building since it has been constructed in phases over the last two years and is therefore not eligible to be considered under Part 11 of the OBC, in particular the alternative measures provision contained therein.)

The first provision, Sentence 3.2.8.4.(4), stipulates that the increased travel distance to exits provided by Clause 3.4.2.5.(1)(c) for a sprinklered floor area does not apply to space within a building above ground level even though sprinkler protection is provided if that same area is within an interconnected floor space. In essence, the effect on the travel distance requirements due to the inclusion of the interconnected floor space within the subject building is as if it did not contain sprinklering, and thus the existing portions of the facility no longer qualify for the extension in permitted travel distance.

As a result, the maximum travel distance permitted for such floors above the ground level is 40 m for the Group D occupancy areas and 30 m for the Group F3 occupancy areas, as based on Clauses 3.4.2.5.(1)(b) and 3.4.2.5.(1)(f) respectively. As noted, the existing travel distances on certain floors of phases 1, 2, and 3 for both administrative and manufacturing areas is 45 m. To compensate for this perceived deficiency, the Applicant is offering certain measures of compensation as outlined in the previous section.

Article 3.2.8.9., the second provision in dispute, requires in Sentence (1) that a smoke control system, designed in conformance with the provisions of the remainder of the Article (Sentences (2) to (8)), be incorporated in a building with an interconnected floor space. Within Sentences 3.2.8.9.(2) to (8) two different types of smoke management systems are set out. Sentence (4) describes a system of zoned smoke control, whereas Sentences (6) and (7) outline a total smoke control system.

The differing characteristics of these systems is that a zone-type smoke control system provides for air exchanges at a rate of six times an hour from the zone in which the fire was detected and that smoke is prevented from moving from one zone to another. With a total smoke control system, on the other hand, air is mechanically exhausted not from individual zones but from the top of the interconnected floor space at a rate of six times an hour, unless the volume of space exceeds 17,000 m3 (600,000 ft3) in which case the air exchange rate need only be four times an hour. Since phases 1 to 3, at 260,513 m3 (9,200,000 ft3), and the large atrium, at 56,633 m3 (2,000,000 ft3), consist of a total of 317,145 m3 (11,200,000 ft3), the subject interconnected floor space far exceeds the threshold which permits four air changes an hour.

However, to install either type of smoke control system in the existing parts of the building would be difficult for the Applicant to achieve. As he stated:

"Both of the two prescribed smoke management options of the OBC would require extensive modifications to the existing air handling systems in the existing buildings. In addition to many smoke dampers, special controls for the operation of the fans would be required. The existing fan and duct sizes in Phase 1 are not suitable for the required air exchange rate. The Phase 1 air handling system would be required to be reconstructed. Where the process air handling system of Phase 2 could be used to accomplish the objective, substantial modifications of the existing building would be required to cover all areas of the floor.

"As such, the introduction of one of the prescriptive options of the OBC would cause significant construction difficulty and business interruption."

As a result, the Applicant has proposed the previously described alternative system of smoke management that he believes is equivalent to those articulated in the prescriptive requirements of the Code.

At issue, therefore, is whether the proposed smoke management system for the atrium which is not prescribed nor recognized by the Code, and the proposed compensating fire safety measures, as specified, offered in lieu of reducing the travel distance within the interconnected floor areas provide sufficiency of compliance with the OBC.

4. Provisions of the Ontario Building Code

Sentences 3.2.8.4. Exits

  1. Except where exits serving the floor area are at ground level, the increased travel distance to exits permitted by Clause 3.4.2.5.(1)(c) shall not apply to a floor area within an interconnected floor space.
  2. Where a portion of a floor area is not within an interconnected floor space, required access to exit from such portion of a floor area shall not lead through an interconnected floor space.

Article 3.2.8.9. Smoke Control

  1. A smoke control system conforming to Sentences (2) to (8) shall be designed to control the movement of smoke within a building containing an interconnected floor space.

  1. The design of the smoke control system shall assume an outdoor temperature equal to the January design temperature on a 2.5% basis.

  1. Upon activation of the sprinkler system or automatic detection of smoke by at least two smoke detectors in a single zone within an interconnected floor space, the system shall
    1. stop air moving fans which provide for the normal exhausting or re-circulating of air in an interconnected floor space,
    2. activate exit stair shaft protection required in Article 3.2.8.4.,
    3. activate elevator protection required in Article 3.2.8.5., and
    4. activate the vestibule air supply required in Sentence 3.2.8.6.(1).

  1. A building containing an interconnected floor space may be designed so that, in the event of a fire arising in a floor area or part of a floor area within the interconnected floor space, automatic detection of such fire will activate air handling equipment that
  1. extracts air directly from such floor area or part of a floor area at the rate of at least 6 air changes per hour, and
  2. supplies air in sufficient quantities and at appropriate locations to prevent smoke from passing out of such floor area into other portions of the interconnected floor space.

5. For purposes of Sentences (6) and (7), the volume of an interconnected floor space need not include the aggregate volume of those floor areas or portions of floor areas designed to have zoned air extraction in accordance with Sentence (4).

6. A mechanical exhaust shall be provided to remove air at the top of an interconnected floor space at the rate of at least 6 air changes per hour, except that where the volume of the interconnected floor space exceeds 17 000 m3 (600,000 ft3), only 4 air changes per hour need be provided.

7. Except where zoned mechanical exhaust described in Sentence (4) has been activated, upon automatic detection of smoke within the volume of the interconnected floor space, the mechanical exhaust described in Sentence (6) shall be automatically activated and supply air shall be provided in sufficient quantity and at appropriate locations to allow a consistent rate of removal of smoke throughout the volume of the interconnected floor space.

8. Overriding manual controls for the smoke control system shall be provided for fire department use at an acceptable location in the vicinity of the fire alarm annunciator.

5. Applicant's Position

A the outset, the Agent for the Applicant submitted that the introduction of an atrium space into the JDS Uniphase building does not compromise the level of safety afforded to the building's occupants. He offered the following arguments to support this assertion.

Prior to this, however, the Agent offered some background information about the subject complex. He noted that phases 1 and 2 are completed and occupied and the construction of phase 3 is well under way. He also noted that phase 4, with its Executive Atrium, will comply in full with the requirements of the OBC. The Agent indicated that the exterior walls of phases 1 to 3, which are to become interior walls, were built to the appropriate construction requirements at the time. He further described the building as having a substantial portion dedicated to office use and that the manufacturing done in the facility produces high-tech electronic components, specifically fibre optics switching cable. This production is highly controlled and not very combustible, he stated.

Regarding the issue of travel distance, the Agent began his argument by noting that "technically" the existing floor areas in phases 1 to 3 are considered as being part of the interconnected floor space, however, this space will be physically separated from the proposed large atrium by the existing walls. And while these walls are not rated, they will act as a screen to control the movement of smoke. This function will be greatly enhanced by the proposed NFPA 92B smoke management system, he argued. Because this system vents out through the roof of the atrium, smoke from a fire on an existing floor area that breaks the smoke screen, or smoke from a fire that originates in the atrium itself, will be expelled to the exterior before it spreads to other parts of the building. In this way, the Agent noted that their NFPA 92B alternative solution regarding the smoke management dispute is also intended as a compensating measure for the travel distance issue.

The Agent then described the serious construction challenges that would be faced if they had to retrofit the existing portions of the building to comply with the reduced travel distance requirements for interconnected floor spaces. In order to meet the 40 and 30 m travel distances for the Group D and F3 occupancies respectively, fire rated exit corridors would have to be extended deep within certain floor areas so as to shorten the access to exits routes. The cost of doing this would be significant, he stated. Besides, according to their calculations the majority of the disputed floor area (roughly 55%) is Group D office and administrative space, which is only 5 m over the required distance, he noted.

Additionally, the Agent argued that F3 occupancies, especially the subject one, are not much more hazardous than D, and the Code recognizes this by permitting similar travel distances for these uses in some circumstances. And since the manufacturing done in this building is quite safe, the lesser distance of 30 m instead of 40 m seems onerous in this instance.

The Agent continued that even if access to exits routes in the affected floor areas could be reduced, it would not quicken the evacuation time because of the width of the exit doors provided on each floor area. As he explained, exit time is comprised of not only the time it takes to get to an exit or access to exit door, but also of the time it takes to get through the door in question. Because, in an emergency, other occupants of a floor area have also moved to the exit door a queue of people will form. The time it takes for this queue to pass through the exit must be added to the time it took to travel across the floor area to the exit. In the case of the subject building, when considering the occupant load, the existing travel distance and, most critically, the width of the access to exit doors, the Agent argued that the overall time to exit would still be approximately the same. In other words, the queue that would form as a result of the width of the exit doors would take sufficient time to funnel through that it would negate the additional travel distance currently in dispute.

In addition, the Agent argued that the entire existing floor space, both D and F3 occupancies, are sprinklered. This will greatly contribute to the safety of those areas and would lessen the hazard of the extra distance required to travel.

On the issue of the proposed smoke management system, the Agent stated that both the solution for atrium (the NFPA 92B system) and the existing building (the smoke screen and the various sprinkler protection) must be viewed as a comprehensive fire safety package. As such, he argued that the total proposal addresses the building - both existing and new - in its entirety (except of course for the phase 4 area). The Agent indicated that he hoped the BCC would assess the project in this holistic fashion. He then described both elements of the proposal.

Because of the sheer volume of air in the atrium and phases 1 to 3 (over 300,000 m3) that the OBC requires to be vented for smoke management purposes, the Agent explained they felt it prudent to explore other alternatives. For the atrium, NFPA 92B was a logical choice since it provides a standard for smoke control in large atria space and offers more flexibility in design than the OBC. Moreover, the principles of the NFPA 92B standard are essentially the same as those in the Code, the Agent argued. Specifically, the methodology of NFPA 92B also follows an engineered approach for smoke management that calculates the maximum rate of exhaust required to maintain the smoke interface above a prescribed level. This is done by predicting the maximum fire size and consequent smoke production likely to happen within a floor area. As part of the smoke production calculation, the NFPA formula takes into account the accompanying sprinkler system and its limiting of smoke generation by suppression of fire. In short, the Agent explained, the approach of NFPA 92B is to curtail smoke generation and propagation by limiting the size of fire through suppression and by providing an equilibrium for the smoke layer interface by exhausting smoke at a rate at which it is supplied by the fire.

The Agent then explained that they created a series of scenarios regarding differing locations for a fire to originate with respect to the atrium. According to their calculations, the worst case scenario was a fire that originated close to the floor level of the atrium. In this scenario, the largest fire size within the atrium would be over 8,000 Btu/second and would take 430 seconds before sprinkler activation. Such a blaze would require approximately 3,734 m3/min (132,000 ft3/min) of exhaust from the top of the atrium. As the Agent noted, this is the same exhaust evacuation rate that they have proposed for this space.

The Agent continued that the NFPA 92B standard also assumes that any potential fire would occur on a single floor area, and not on more than one area simultaneously. This assumption also applies to the relationship between the floor areas and the atrium, i.e. the smoke management system is designed assuming that a fire would not occur in a floor area and concurrently in the atrium. This is a significant assumption in terms of the comprehensive approach of the proposal, the Agent noted, and it supports the concept that the existing and new portions of the building are taken in conjunction with each other and function together. Further, since the chance of fires starting in two separate areas of the building is quite remote, such an assumption is safe and rational.

It must be appreciated therefore that the smoke screen is an essential component for the two areas in regards to controlling the movement of smoke, the Agent indicated. Protecting the screen thus is vital to maintaining the integrity of the separation. Due to the fact that the smoke separation is a former exterior wall, it will perform well as a screen, he added. These walls have the capability of preventing the migration of smoke between the atrium and adjacent floor areas until the heat from the fire is intense enough to break them. This is more likely to happen if a fire originates immediately adjacent to the glazing, he noted. It is for this reason that the curtain wall is to be protected with close-spaced sprinklers installed beneath a 300 mm wide baffle located around the perimeter of the atrium area.

With respect to the existing floor areas, the Agent stated that in this case they are again faced with an situation where extensive and disruptive modifications are needed to bring about the changes required to meet either of the types of Code compliant smoke control systems. The existing air handling system, he noted, does not have the capacity to perform to the level required for smoke management in an interconnected floor space. The existing curtain walls, however, will protect these areas. Indeed, these walls, as a physical barrier between the spaces, represents an excellent passive safety system. And passive systems, the Agent argued, are always superior to active, or mechanical, ones. The Agent reiterated that the smoke screen will be sprinkler protected. In addition, he noted that the existing floor areas are safe since they enjoy complete protection offered by sprinkler, fire alarm and standpipe and hose systems as per Code.

Lastly, the Agent noted that he has been involved with projects in which NFPA 92B has been employed in other large buildings elsewhere in the province and in the country such as the Air Canada Centre in Toronto, the Corel Centre in Ottawa and GM Place in Vancouver. In his view, NFPA 92B is appropriate for the JDS Uniphase building. And added to the safety brought to the building by the NFPA 92B smoke management system is the safety factor of the curtain wall smoke separation, which is a passive safety feature. These systems, together with the other Code complying safety features, led the Agent to conclude that the objectives of the OBC for areas within an interconnected floor space have been met with their overall approach to fire safety within the structure.

6. Respondent's Position

The Respondent commenced their presentation with some of their own background of the project. They noted that the entire project was presented to municipal officials prior to development of the site and construction of any of the phases, therefore, they see no reason why the Applicants and their Agents did not foresee the two issues at hand.

On the matter of travel distance, the Respondent submitted that they tried to see this as an equivalency issue, but they came to the conclusion that it is not. In their view, it is a sufficiency of compliance issue because the proposal does not comply with the prescriptive requirements of the Code. As he stated, the travel distances, now that they are to be contained within an interconnected floor space, are deficient. Whereas he acknowledged that the Group D areas are only somewhat deficient, the F2 areas, at 50 % over the allowable distance, are a long way from meeting the Code. The Respondent also indicated that he disputed the floor area percentages the Agent outlined. He argued that the F3 occupancy, where the deficiency is greater, has the larger floor area.

In terms of the smoke management issue, the Respondent made the following statement:

"The Nepean Building Division has reviewed the Report to attempt to establish an equivalency as permitted under Section 2.7.2.2. of the Code for systems. Although NFPA 92B is not a referenced document under 2.6 of the Code it can be considered to have some validity in the prediction of smoke production and design of smoke management in atria. Although the use of NFPA 92B may be considered as the basis for an equivalency to the prescriptive requirements for smoke control found in 3.2.8.9. of the Ontario Building Code (for the atrium), it does not provide an equivalency for the required 2 hour vertical fire separation for the existing complex. Clearly, the additional mitigating measures proposed to further protect the smoke separation (existing exterior wall) ie. closed space sprinklers & heat baffles, used to limit smoke movement must be considered as an application for sufficiency of compliance and outside the regulatory framework provided under the Ontario Building Code."

In other words, while they felt they could offer qualified support for the proposal to install an NFPA 92B compliant smoke control system as an alternative solution in the atrium area, they felt that the proposed measures intended to address the issue of upgrading the smoke management system in the existing areas was a concept they felt they had no authority over.

7. Commission Ruling

It is the decision of the Building Code Commission that at the JDS Uniphase building, 3000 Merivale Road, Nepean, Ontario:

  1. Sufficiency of compliance with Sentence 3.2.8.4.(4) of the OBC is provided with respect to the proposed 45 m travel distance in the office occupancy areas; however,

  1. Sufficiency of compliance with Sentence 3.2.8.4.(4) is not provided regarding the proposed 45 m travel distance in the manufacturing occupancy areas.

It is also the decision of the Building Code Commission that at the JDS Uniphase building, 3000 Merivale Road, Nepean, Ontario, the proposed smoke management system designed in conformance with NFPA 92B, "Guide to Smoke Management in Malls, Atria and Large Areas", and intended for the proposed atrium to be constructed adjoining to the existing building, provides sufficiency of compliance with Article 3.2.8.9. of the OBC.

8. Reasons

Re: Proposed Travel Distances in the Group D Office Occupancy Areas

i. The travel distance proposed for the Group D areas, at 45 m, is only slightly over the required travel distance of 40 m.

ii. The smoke separation provided by the existing (formerly exterior) curtain walls that are to face the atrium, the smoke exhaust system proposed for the atrium and the closely-spaced sprinklers around the atrium perimeter are adequate to mitigate the excess travel distance proposed.

Re: Proposed Travel Distances in the Group F3 Manufacturing Occupancy Areas

iii. The travel distance proposed for the Group F3 areas, at 45 m, exceed the Code requirement of 30 m by 50 % and the proposed compensating measures (described in reason ii above) were not considered commensurate with such an increase of permitted egress distance.

Re: Proposed Smoke Management System

iv. In the present circumstance, the utilization of a smoke management system designed on NFPA 92B is an acceptable alternative to the prescriptive requirements of OBC Article 3.2.8.9.

v. The NFPA - 92B standard is based on sound engineering practices and its requirements have been satisfied in the Applicant's proposal.

Dated at Toronto this 18 th day in the month of May in the year 2000 for application number 2000-32.



_________________________________________________________________

Mr. Kenneth Peaker, Chair-Designate





_________________________________________________________________

Mr. John Guthrie





_________________________________________________________________

Mr. Fred Barkhouse