Which aspect does not typically influence system performance benchmarks?

System performance benchmarks are primarily influenced by factors that relate directly to the design, operation, and expected performance of the systems being assessed. Historical building performance data provides insights into how similar systems have functioned in the past, allowing for comparisons and setting realistic expectations. Manufacturer specifications outline the performance limits and capabilities of equipment, serving as a guideline for what benchmarks should be set based on engineered design. Industry standards establish the baseline requirements and best practices for performance in various systems, ensuring consistency across the sector.

In contrast, employee productivity levels do not have a direct impact on the mechanical or operational performance of building systems. While overall productivity may be influenced by working conditions and system efficiency, it is more of an outcome of system performance rather than a benchmark for measuring it. Thus, employee productivity levels stand apart from the other options, which are more closely tied to the technical metrics that define system performance standards.