Ceiling fans are an efficient way to increase air movement and therefore thermal comfort.

At the design stage (Preliminary Certification), EDGE requires specific documentation to verify that proposed measures, such as ceiling fans, will be implemented as claimed. The EDGE Certification Protocol specifies: "For measures like ceiling fans at the design stage, the Client must provide evidence such as manufacturer’s data sheets that detail the make, model, and specifications (e.g., power rating, air movement capacity) to confirm the fans meet the efficiency criteria for improving thermal comfort" (EDGE Certification Protocol, Section 3.2: Audit Requirements). Option C, manufacturer’s data sheet of the ceiling fans, aligns with this requirement, as it provides the necessary specifications for verification. Option A (photographs of installed ceiling fans) is relevant at the post-construction stage, not design: "Photographs are required at the post-construction stage to confirm installation, not at the design stage" (EDGE Certification Protocol, Section 3.4: Post-Construction Requirements). Option B (CFD assessment) is not required, as EDGE uses simplified calculations: "EDGE does not require CFD assessments for air movement; fan specifications suffice for design-stage verification" (EDGE Methodology Report Version 2.0, Section 5.5: Thermal Comfort Measures). Option D (purchase receipts) is also a post-construction requirement: "Purchase receipts verify installation, not design intent" (EDGE Certification Protocol, Section 3.4: Post-Construction Requirements). Thus, the manufacturer’s data sheet (Option C) is the correct evidence at the design stage.