WestCon Tribune

 

STANDARD OF CARE
Presented by Joshua Kardon, SE
Joshua B. Kardon + Company Structural Engineers

The evening passed by quickly with the presentation and audience participation. An outstanding handout was made available which also served as a guide to follow along with the presentation.

Mr. Kardon introduced his talk with a brief discussion of error; the sources and acceptability of error "When you hire an engineer you buy the *engineer 's normal errors. You are responsible for damages arising from your engineer's non-negligent errors. The engineer is responsible for damages arising from his negligent errors, and the line between negligent and non-negligent error is the "standard of care". (*References to "engineer" were explained to be equally applicable to other architects, contractors, consultants or experts.)

It is the duty of a professional in performing professional services for a client to have that degree of learning and skill ordinarily possessed by reputable peers practicing in the same or similar locality and under similar circumstances. It is the professional's further duty to use the care and skill ordinarily used in like cases by reputable members of the profession practicing in the same or similar locality under similar circumstances and to use reasonable diligence and best judgement in the exercise of professional skill and in the application of learning, in an effort to accomplish the purpose for which he was employed. A failure to fulfill any such duty is negligence.

After pouring the foundation for the discussion, Mr. Kardon continued with the framing of a number of case studies to further the understanding of the Standard of Care in Engineering. The following is a summary taken from the hand out.

In a steel frame design of two, two-story 5-bay steel frames, the engineer of record produced five lines of calculations for one frame, one line of calculations for the other. The calculations did not address vertical loads on the frames, and did not evaluate drift (seismic deflection). The frame as originally designed was adequate in terms of stiffness and strength for code-required loads. The analysis showed the frames were a very efficient and economical design. The illustrations of the case study showed that calculations are not engineering; the calculations substantiate the engineering design.

In an example Mr. Kardon used of a retaining wall, a design of pre-cast block modules and geotextile was assembled into a reinforced earth-type ground support structure. The vendor-provided "design calculations" were flawed in concept and detail. The engineer, who had not done retaining walls in the past, used these calculations and the walls failed in heavy El Nino rains. An experienced expert described the project engineer as negligent. The standard of care is not defined as what the expert does. The wall might have failed anyway because of the abnormal rainfall, but by using and displaying judgement and diligence, the designer would not have been professionally negligent.

In the case of a foundation design for a large condominium project, units in phases V and VI are the subjects of lawsuits arising from leaks in windows and cracks in the walls. The design engineer was sued for negligence because the engineer did not carry forward the soils engineer's Phase IV recommendations. Management and control of information are part of good engineering practice.

The collapse of an unreinforced masonry building included the requirement for the general contractor to produce shoring and bracing plans. The work took place without those plans and construction took place without the knowledge of the engineer. The engineer was excluded from the construction process, including the review of shoring and bracing plans, by the owner and the contractor.

Due to the absence of shoring and bracing, a brick wall collapsed during construction, killing the contractor's foreman. The engineer was sued for professional negligence and wrongful death. The expert for the plaintiff testified the engineer was negligent for not indicating on the plans that shoring and bracing was required for the specific wall which later collapsed. The jury found the engineer not negligent or liable because the owner and contractor prevented him from fulfilling his obligation to exercise care and diligence. The jury found the owner and the contractor liable and made a monetary award to the family.

In 1942, wind induced oscillations destroyed the new Tahoma Narrows suspension bridge. One hundred years earlier, the dangerous dynamic effects of the wind were known, and suspension bridge design included measures to counter those effects. The engineer for the superstructure was not thought to be negligent. Twentieth century bridge design and construction was apparently thought to be different enough from that of the 19th century that the designer of the Tacoma Narrows Bridge was not held to the standard of care of the earlier era.

Mr. Kardon also cited the Hyatt Regency incident in Kansas City. In this case a minor, "non-structural" feature of the hotel collapsed suddenly, killing and injuring a large number of people. The connection detail failed because it was not carried out as the design engineer specified, but was changed for constructability reasons. The structural engineer was found to be negligent for failing to catch and correct the defect in the contractor's change.

After the CitiCorp Building in New York was completed and occupied, the design engineer reviewed the frame for adequacy against "cross-corner" winds. Under those conditions, the building was shown to have a small but unacceptable probability of collapse. Work to strengthen the building was carried out. The engineer's design was not considered negligent, despite the failure to account for the critical loading condition because the engineer exercised an acceptable degree of care and diligence.

In the design of a light tower on the Olympic Stadium in Atlanta, Georgia, the structural engineer of record discovered an error. The engineer told the Architect, who was his client, of the error and designed a correction. The engineer was not aware of the progress of construction, and did not consider the error and the repair an emergency. Without the knowledge of the engineer, construction had progressed to the point that the light tower was being erected ten days after the architect had been informed of the need for the repair. The repairs had not been carried out by that time and when the tower was being erected, it collapsed, killing one ironworker and injuring another.

The engineer's registration was suspended and he was sued for wrongful death. Professional negligence alleged by the plaintiffs was that the engineer's failure to "explicitly indicate to the project manager that emergency action was required". The error in the design was not negligent, but the lack of urgency in the engineer's response to uncovering the error was.

The "Swinging Bridge" was a pedestrian suspension bridge popular among visitors and residents because by coordinating their movement, they could force it to swing. In 1982, an engineer reviewed the structural condition of the bridge and determined it was in good shape. In 1989, the bridge collapsed while being forced to swing by pedestrians and five people were killed and many were hurt.

The victims and families of those killed sued the county and the engineer, charging them with failure to warn of the hazard presented by the bridge. The court ruled for the defense, stating, "Mere knowledge of danger to the individual does not create an affirmative duty to protect."

The pedestrians caused the collapse and there was no negligence on the part of the county or the engineer who reviewed the bridge.

As expected, given these diverse examples of engineering performance, a lively exchange of questions and answers took place throughout, highlighting the presentation. Mr. Kardon's presentation has opened the door to our two-part discussion on Standard of Care. For the month of July, Mr. Eugene Bass, also a Westcon member and practicing attorney with a civil engineering background will continue on with the same topic but from a different vantage point.

Mr. Kardon will also be at our July meeting, along with Mr. Bass to answer questions.