THE DEFINITION OF CLASSES OF AREA WITHIN BUILDINGS IS DEALT WITH IN THIS STUDY. THE OBJECTIVE OF THE STUDY WAS TO EVALUATE EXISTING METHODS OF CATEGORIZING AREAS IN BUILDINGS, FOR PERTINENCY TO THE REQUIREMENTS OF FEDERAL AGENCIES. A TASK GROUP OF SPECIALLY QUALIFIED INDIVIDUALS WAS NAMED BY THE OPERATING COUNCIL TO UNDERTAKE THE STUDY WHICH LED TO THIS REPORT. FOLLOWING THE INTRODUCTION THERE ARE THREE REPORT SECTIONS--(1) RECOMMENDATIONS OF THE TASK GROUP, (2) CRITERIA FOR CLASSIFYING, DEFINING AND MEASURING GROSS AREAS, NET ASSIGNABLE AREAS, CUSTODIAL AREAS, CIRCULATION AREAS, MECHANICAL AREAS AND CONSTRUCTION AREAS, AND (3) SUPPLEMENTARY INFORMATION. THE LATTER SECTION IS PRESENTED IN THE SUBJECT ORDER AS THE RECOMMENDATIONS AND PROVIDES AMPLIFICATION AND/OR EXPLANATION. THIS DOCUMENT IS AVAILABLE AS PUBLICATION 1235 FROM THE NATIONAL ACADEMY OF SCIENCES, NATIONAL RESEARCH COUNCIL, WASHINGTON, D. C. FOR $2.00. (RK)