What is the maximum test pressure allowed as specified by ISO 9972:2015?

The maximum test pressure allowed as specified by ISO 9972:2015 is 100 Pa. This standard outlines the methodology for determining airflow rates and airtightness of buildings. The chosen pressure level is significant because it represents a balance between achieving accurate measurements of a building's tightness while ensuring that the test does not impose excessive stress on the building structure.

Using a test pressure of 100 Pa allows for a reliable assessment of the building's performance in real-world conditions, simulating typical wind pressures that buildings might encounter. This level is part of a standardized approach that enables comparisons across different buildings and testing scenarios, ultimately aiding in achieving better energy efficiency and indoor air quality.

The other options indicate pressures that are lower than the established maximum in the ISO standard, which would not provide the same level of insight or comprehensive data regarding a building's airtightness under standardized testing conditions.