"Comparison field","Offer A","Offer B","Interpretation"
"Named model and document","","","Keep exact fan and source revision"
"Airflow and unit at rating point","","","Same intended aerodynamic duty required"
"Static pressure and unit","","","Do not compare different duty points as equivalents"
"Fan speed and installation type","","","Record the rated configuration"
"Acoustic quantity: Lw or Lp","","","Source power and receiver pressure are different quantities"
"Reference quantity and reported units","","","Preserve supplier definition"
"Band data or combined weighting","","","A-weighting alone does not identify power/pressure"
"Source inlet/outlet/total basis","","","Do not substitute one emission basis for another"
"Receiver distance and direction, if Lp","","","Missing receiver conditions prevent like comparison"
"Reflections, background and measurement conditions","","","Retain the conditions, not only the dB value"
"Fictional energetic sum","Contribution 1: 60 dB","Contribution 2: 60 dB","Same receiver/basis; independent contributions; stable comparable conditions. Combined 63.0103 dB, about 63; not 120"
"Like-for-like comparison supported?","","","Manual conclusion; identify missing quantity or different duty"
"Question for supplier or acoustic specialist","","","Separate offer comparison from receiver prediction and acceptance"
"Use","Manual worksheet; no formulas. Import UTF-8 with comma separators; widen columns and wrap text. Save an editable spreadsheet copy. Enter supplied evidence in blank fields; use not supplied for missing records. Examples are not your project results.","No formulas, site model or safe-exposure threshold.","Do not use an unmatched power-minus-pressure difference to rank fans"
"Source context","https://ask.ifas.ufl.edu/publication/AE020","https://webcontent.greenheck.com/atg-cms-v2-prod/docs/default-source/resource-library/white-papers/fa-121-23_basicsfansound.pdf?sfvrsn=62c9205e_1","https://www.greenheck.com/resources/blog/understanding-fan-sound--sound-power--testing--and-ratings"