The BPI energy auditor training course prepares individuals to understand the various components of building science, including combustion safety, blower door testing, energy analysis, and home performance assessments.
Key difference: The two paper sizes are used for different purposes in different countries. A4 paper is part of 'ISO 216-series' , while the Letter paper is a part of the old 'American National Standard Institute'. A4 is an internationally recognized paper size that measures 8.27 inches wide and 11.69 inches tall. All âAâ sizes has an aspect ratio of 1: â 2 (square root of 2).
Flats (Large Letter) The US flats postage rate is for large envelopes, as used when sending a document of letter or legal size or a magazine through the post. To qualify as a flat the item must have one dimension that is outside of the maximum for letter and comply with the following maximum dimensions. Size 16 envelopes qualify as flats as do the catalog envelope sizes 1Â¾, 3, 6, 8, 9Â¾, 10Â½, 12Â½, 13Â½, 14Â½, 15, 15Â½.