Canadian Consulting Engineer

Performing better

May 1, 1999
By John Ivison, P.Eng., CP

Over the last 30 years building codes and standards have become increasingly complex, reflecting a rise in the public expectation of how safe buildings should be. Also, the increase in construction-re...

Over the last 30 years building codes and standards have become increasingly complex, reflecting a rise in the public expectation of how safe buildings should be. Also, the increase in construction-related litigation has necessitated the broadening of codes and standards into a legal framework that defines the responsibility and liability of various industry players. Recently there has been a shift towards performance codes which will provide a more fundamental engineering, or “objective-based,” approach to achieving fire safety.

In the performance-based approach to fire safety the end result is more important than the means for achieving it. In other words, as long as the designer can show that the building will provide the level of safety intended by the codes and standards, he or she does not necessarily have to make the building features conform to the prescriptive formulas in the building code.

Government legislation adopts written requirements for constructing buildings. These codes, such as the National Building Code of Canada, have evolved over time, but have traditionally defined the general construction requirements for things such as building size, building area, and the type of construction. Before the end of the Second World War the focus was on preventing structural collapse and confining fires to the floor or building where they originated. The requirements for fire and life safety have expanded as large fires have shown that safety within compartments is as important, if not more so, than containing fires.

Since the 1970s the scope and complexity of high-rise buildings and those with interconnected floor spaces dictated the need for more study of smoke and fire behaviour in interior spaces. Modern high-rises, for instance, have a wide array of active fire suppression, detection and smoke handling systems, in addition to traditional passive methods of restricting the spread of fire.

The responsibility for designing such systems has also changed. Up until the early 1980s insurers’ engineers played a major role in assessing fire risks inside buildings and in the community at large. In the last 20 years, however, their role has been eclipsed by new fire and building regulations that regulate stricter standards of safety. Building specifications have become increasingly complex. Whereas at one time specifications on the building drawings were enough to define the owner’s needs, today the building designers usually compile complex written specifications to define all the building components and systems.

What brought on these shifts in practice? A variety of factors. Certainly one factor is that litigation from construction losses was increasing. Another is that regulatory agencies were expanding in response to increased construction activity. A third factor was the need for a specific standard to enable the building authorities to enforce the stipulated level of performance. Lastly, to some extent, deregulation of the construction industry has necessitated more control of the trades in order to assure owners and the public that installation of systems and equipment is being done to a required standard. These changes in turn created a business opportunity for engineers to design or specify systems to meet the referenced standards.

Falling between the cracks

All building specifications refer to codes and standards. Traditional performance specifications may have referred, for example, to “the latest edition of NFPA 13 Standard for the Installation of Automatic Sprinkler Systems.” This reference meant that the latest standard should be used which reflected advancements in methods, materials and standards of safety.

Today, however, the former practice has been largely abandoned, and instead of referring loosely to “the latest edition” of a standard, the specifications refer to a legally adopted standard. The building codes have been expanded to include numerous referenced standards by edition, i.e. the references include the year of publication. These requirements are then entrenched in law when the provinces and territories adopt their building codes. A problem arises in that many of the referenced standards run out of date or are revised during the periods between the adoption of different editions of the building codes.

While the building regulations embody the building requirements and duties of the engineer in written or statutory form, a problem comes when there are allegations of negligence or breach of a duty of reasonable care. In terms of liability, the courts may deem that a reasonable engineer would be familiar with the latest edition of codes and standards and would therefore be bound to incorporate those requirements in the design — particularly where protection of the public is concerned.

Thus the engineer has the dilemma of deciding whether he or she has a statutory duty to abide by the construction laws (the building codes) on the one hand, or has a duty to protect the public on the other. For example, if the latest standard is revised to eliminate certain hazards that have been identified following the analysis of fires, there is a potential liability in continuing to use the old edition of the standard, even though that is the standard incorporated into the building code.

The contractor may be adequately protected by his written contract, i.e. to construct to the specific issue of a standard, but the engineer may not be similarly protected since he or she has a duty of care which may deem that he should have used the latest edition of a standard. Though the professionals can protect themselves through agreements and written contracts with owners, the use of outdated standards in prescriptive codes represents a potential legal pothole for them.

By contrast, in high risk industrial industries where insurers have a more traditional role in defining the construction requirements, the latest edition of standards are routinely used even though these may differ from those established in the building codes. Here again, though, the practice may present problems if the facilities are in regions where permits are processed through building authorities that use a different edition of the standard in their regulation.

In reality, the more complex the facility is, the more likely it is that the latest rather than the referenced standards will be used. While there is a freedom to use “good fire protection engineering practice” under the building codes provisions for Special (i.e. unusual) Structures, potential liability arises if the authorities and engineers disagree over what is the appropriate standard to use — for example, where the most recent standard is less onerous than the one referenced in the building code. The complexity of codes and standards in industrial applications partly explains why the authorities are reluctant to use their full power in regulating work associated with some industrial plants.

Under a performance-based system the above problem theoretically disappears since the designer has the freedom to design as he or she sees fit in order to achieve a level of fire and life safety. The prescriptive system can be used as a “test and balance” of the chosen solution, but the question of which standard is referenced is legally less of an issue.

We expect that many prescriptive standards in use today will survive but will evolve to include performance objectives. One example is NFPA 13, the sprinkler standard which, as the fundamentals of extinguishment become known and quantified, may be modified to include new calculation methods for use by design professionals.

Ideally the design professions will regulate themselves under a performance-based system, rather than increasing the industry’s dependence on authorities. Committees of peers acting through the auspices of the professional associations, for instance, may identify industry problems and issue bulletins or formal interpretations representing the consensus approach to specific problems. This system is likely to respond more quickly to problems than the current prescriptive system involving t
he building codes cycle which is normally five to eight years.

Professional associations can therefore take a very proactive role by establishing their own infrastructure for dealing with practice requirements under performance-based codes. The regulatory authorities also can be represented on these committees to enhance the co-ordination between various industry players.

Back to school

The current prescriptive system has engendered a system that relies heavily on enforcing compliance. The shift in responsibility from insurers to building authorities often led to the municipalities having a scarcity of experts able to evaluate fire performance. The shortage has led in turn to the reliance on prescriptive provisions of the code, while the use of design as a flexible tool for achieving specific performance objectives has been discouraged. The use of prescriptive codes as a benchmark in litigation has reinforced this trend.

It is clear that in order to move to a performance-based system, professionals will need to have a broad understanding of the fire engineering principles that underlie the building codes, as well as experience in applying prescriptive solutions. There is an opportunity for engineers and firms who have experience applying prescriptive codes to acquire new performance techniques and to capitalize on the benefits of the modified regulatory environment. Consulting fire protection engineers, for example, obviously form a group that could partly fill the need for expertise in performance-based design.

Due to the sheer numbers of engineers employed in administrating building regulations, they are positioned to play a significant role in the modified performance based fire safety environment.

However, the resistance to performance based codes is significant. It is due to the administrative machinery and investment in human resources that have assembled round the prescriptive system. The challenge to overcome is a great one, but if it is fully met, it will thrust Canada ahead of the other players competing in a global construction market.

The way forward

The transition to performance-based codes requires more analysis of fire risk in buildings. Currently new building construction addresses fire risk only in general terms by defining construction requirements relative to “occupancy.” But fire risk requires an understanding of the complex hazards and risks arising from different processes and operations, and of the spread of fire by contents and construction materials. The fire risk in occupied buildings falls under the auspices of the “fire code” rather than the building code. The fire regulations are generally administered by the provincial fire authorities who may investigate fires directly or through the authority delegated to municipalities, whereas the building codes are administered by building authorities, provincially and municipally. Since the validation of building and community fire models depends upon data from actual fires there is a fundamental need to integrate fire safety regulations (or fire codes) with building codes. Federally this process is already under way.

As a first step, education and training needs at all levels of the fire and life safety industry must be assessed in order to design training programs that will benefit more than one group. Once programs are streamlined and recognized by the various industry participants, they can be delivered at a national, provincial or local level depending on the expertise required. The National Research Council will likely encourage cross-Canada workshops in performance-based design in order to demonstrate fire risk assessment and related design techniques.

In conclusion, the move to a performance-based system requires a fundamental shift in focus for professionals, code authorities and other players. Yet the opportunities for consulting engineers are considerable. Not only does a performance-based system lessen the liability problems that can arise from prescriptive code references, but it also allows a much greater flexibility and intuitive approach to building design. The extent to which Canadian engineers and building designers embrace this new approach will largely determine whether they remain at the forefront in construction expertise on the world stage.

John Ivison, P.Eng., CP is an adjunct professor in chemical engineering at the University of British Columbia. He is a principal of Global Window, consultants in distance delivery of fire protection engineering programs, tel. (604) 682-0388.


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