Canadian Consulting Engineer

Beyond Band-Aids

As electrical engineers specializing in hospitals, we often see projects where a single system such as the generator, electrical distribution, fire alarm or nurse call system is being upgraded or repl...

May 1, 2001  By Kevin C. Cheong, P. Eng.

As electrical engineers specializing in hospitals, we often see projects where a single system such as the generator, electrical distribution, fire alarm or nurse call system is being upgraded or replaced. We also see similar retrofits done in areas such as fire separations, sprinklers, standpipe, and ventilation control, as well as changes made to the building structure for seismic reasons, or for the seismic restraint of equipment.

Sometimes it makes sense that these systems are replaced or updated individually, but often piecemeal improvements don’t lead to the best solution. Many systems are interdependent, and upgrading one without upgrading the others can lead to compromises, or to costly projects to rehabilitate equipment that is obsolete and inevitably has to be replaced soon after.

Almost all systems that require automated controls are now run by microprocessor based controllers that are capable of communicating to other controllers. Many systems are also capable of extension to perform functions beyond their traditional roles. For example, Vancouver’s latest light rapid transit system stations are effectively being monitored and controlled by a fire alarm. Fire alarms are routinely cross-listed for use as security systems and are commonly used as such. Fire alarms are, after all, essentially programmable logic controllers (PLCs). The only difference is that fire alarms have to be approved by far more regulatory bodies.

A common tandem of microprocessor based systems in buildings involves fire alarms and ventilation controls — usually called building automation systems (BAS), or direct digital control (DDC). When there are two systems capable of intercommunication and extension in a facility, the designer or owner often has to choose which one should perform a particular function in order to provide the optimal use of resources. If one system is upgraded, but the other is not, the choice often becomes decision by default because one system is being altered extensively and the other is nearing the end of its life. To complicate the situation, the two systems tend to be the responsibility of two different trades, and/or two different maintenance groups.

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During a fire, especially in high-rises and hospitals, the mechanical ventilation system is usually involved in controlling the movement of smoke within the building. Fans that may move smoke from a compartment that is in a fire condition to a compartment that would otherwise be smoke-free have to be shut down. Fans that pressurize a stairwell or other compartment to prevent smoke migrating in have to start.

The sequence of control of a particular fan is usually initiated at the fire alarm, but the ultimate control, in a typical building, can be either directly by the fire alarm, or indirectly by the BAS. Fan control is considered an ancillary system under the Underwriters’ Laboratories of Canada fire alarm code and therefore is not mandated by that code.

If the building has a building automation system and fan control is done directly by the fire alarm system, the BAS might be put into a trouble status because the fans don’t behave as the BAS expects. If fan control is performed by the BAS, on the other hand, there is one more piece of equipment and one more group of programmers that become involved in an already complex sequence. While I personally recommend having the BAS control the fans because I feel the mechanical engineers are best equipped to understand fan control, I know of a number of electrical engineers who are uncomfortable with anything but direct fire alarm control.

Another example of systems that interact are sprinklers and fire alarms. If a building is sprinklered, then the heat detectors that would otherwise be required can be left out. The number of fire alarm zones that the building is broken down into can also be reduced. The relaxed requirements that go with sprinklering are based on the fact that sprinklers not only detect a fire, but also suppress it and protect fire separations. Conversely, a typical sprinkler system relies on the fire alarm to monitor it for problems that could affect the correct operation of the sprinklers. The fire alarm typically supervises problems such as loss of power to a fire pump, or closure of an isolation valve. If, therefore, a sprinkler system is upgraded before a fire alarm, the old fire alarm may have to be modified. And if a fire alarm is upgraded before a sprinkler system is installed, relaxations in the rules such as those mentioned above cannot be incorporated into the fire alarm system.

Nurse call systems and security systems also are often interconnected to fire alarm systems to notify nursing staff of fire emergencies, or to ensure that people are not trapped by locked doors. A common problem we encounter is secure doors that do not release according to code requirements.

Too little too late

When we are involved in a fire alarm upgrade project and encounter a problem in a related system, there is usually no mandate to correct the problem in the other system. We often uncover code compliance issues, but it is usually too late to correct them within the scope of the project. The problems can range from relatively straightforward electrical wiring problems to major building code problems. If there is a solution available within the scope of the project, often it is not the best one. It is not ideal, for example, to add lighting, closed circuit television, an alarm system and cardkey access to an entrance when instead the entrance could be modified architecturally to eliminate a security risk.

Upgrades tend to occur in waves. Years of underfunding and neglect of a building’s infrastructure systems accumulate until band-aid solutions become obviously just that, repairs are expensive or time-consuming, and reliability is a major issue.

Owners are persuaded to do piecemeal updates or to replace single systems rather than overhaul a group of systems, for several reasons. First, the owner often wants to keep capital costs down in order to undertake the project. Replacing just one system tends to minimize the cost, and some vendors make the initial pricing of update offerings reasonable.

But while the initial pricing of an update versus a replacement is often lower, its life expectancy is usually lower. Also, any old parts that are not replaced remain problematic. In some cases clients are encouraged to update the central controller of a system, for example, but not the field devices. In some cases a system will accommodate devices from a different vendor, but then compatibility issues may arise and neither vendor can be expected to be fully responsible.

Often as a product approaches the end of its life, the price rises dramatically for both maintenance and additions or changes. For systems like fire alarms, the manufacturer becomes an owner’s sole source supplier because parts are rarely interchangeable and often only the manufacturer can reprogram the system. Suppliers have to keep prices for new equipment low in order to be competitive, so they tend to make their profits on modifications and maintenance.

Vendors often will suggest upgrading to a new product that requires less maintenance and is less expensive to modify as building renovations occur. The vendor will frequently provide the client with a cost estimate based on other projects. These estimates may lead to further problems. A vendor cannot be expected to do a thorough review of the prevailing conditions at one facility compared to another. Vendors are not qualified designers or quantity surveyors, and they are pressured to provide estimates based on the most attractive capital cost. Vendors are also typically oriented to a single system and estimate as such. They don’t necessarily allow for associated costs such as design fees, related equipment, or facility personnel costs because they do not routinely see these. As well, owners often encourage underestimating by assuming that a higher estimate is due to a vendor’s equipment cost rather than allowances for other items. As a result, the upgrades they c
hoose start out underfunded.

A far better approach at this preliminary stage is to involve a competent consultant to provide an objective and more thorough evaluation. While a vendor will usually provide an estimate for free, consultants won’t work for free but will often price their services at an artificially low price, hedging on the fact that they will have an advantage if the project proceeds. Unfortunately even with low prices, owners are often hesitant to spend money on studies that may not lead to a project in the immediate future.

The cost of a study is rarely wasted, since the systems usually are replaced eventually and all that is required then are updates to the original study. We have updated studies for some buildings three times before the studies became actual projects. Ideally, the consultants involved will be familiar with the building code and systems that may be affected by the one being upgraded. The consultants should also be accustomed to working in the capacity of prime consultant, since they will lead the work and be responsible for knowing when it is necessary to bring in other expertise. Many designers are relying heavily on suppliers to do work that traditionally would be considered their own, and as a result they are sacrificing objectivity. Meanwhile, the suppliers, who are essentially forced to work for free, have to limit their involvement if they hope to make any money. It is important for designers and owners to realize this.

Ideally, therefore, plans and budgets for upgrade projects should take into account the integration and coordination of different systems and the associated work. We recently did a hospital project that started out by upgrading a fire alarm as demanded by the local authority and ended up encompassing the sprinkler, security, nurse call systems and related sub-systems such as monitoring patient wandering, wireless telephones and access control. From a value perspective, it simply made sense to upgrade all the systems together rather than doing one at a time over the next few years as each system became unserviceable. On another project, building code, ventilation, sprinkler, fire alarm, and security systems were upgraded simultaneously as intended from the outset and this gave us flexibility in solving existing problems. While hospitals are more complex and involve more systems than other types of facilities, the same issues arise, only on a smaller scale, in most commercial buildings, and certainly in every high-rise.

In summary, it is common to upgrade only one system at a time because the cost appears more palatable, but the best value is usually derived when a group of related systems are upgraded together. Combined upgrades allow the owner and designer flexibility in solving problems and avoiding expensive short-term alterations to obsolete systems. CCE

Kevin Cheong, P.Eng. is an electrical engineer with Robert Freundlich & Associates, Vancouver

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