MALB_2014 with 1-21 Revisions

Normative Appendix A ANSI/AARST MALB-2014 with 1/21 Revisions A— Reporting Building Operating Conditions 4 Table A-0 Climate Zone Overview—Quick Reference* * More detail for each climate zone is provided in the following tables. * Home (Hm) is based on 24 hour temperature averages. Work (Wk) is based daytime temperatures only. Note—For discussion purposes, this table illustrates both: 1) Seasonal expectations, and 2) Expected percentages of time that different building operating conditions occur across test periods of multiple days, weeks or months when the outdoor temperature average across the test period is nominally equal to any temperature shown in the table. Each operating condition influences test results. The measured concentration in each building or unique sector within a building across any span of time is the product of dynamic interactions between factors that include: building capacity for stack effect strength; soil permeability that relates to the volume of soil gas available to enter a building; natural (closed building) ventilation rates with outdoor air; and both natural and mechanical air distribution within the building.