Supplement to ASHRAE Laboratory Design Guide: Planning and Operation of Laboratory HVAC Systems, 2nd Ed.

This document provides background information to help classify, design, and operate LACSs according to the LVDL table included in the appendix (Table 3). The table describes criteria, design attributes, and operating specifications associated with each LVDL. The purpose of the LVDL classification system and Table A are to foster communication between stakeholders when evaluating the protective capability of an existing LACS or during discussions about design, construction, and operation of a new LACS intended to manage and control airborne chemical hazards.