The IIAR Critical Task Guidance for Ammonia Refrigeration System Emergency Planning, 1st Edition was published to assist employers, government regulators, and public safety emergency responders in preparing emergency procedures to avoid and address ammonia incidents. The guideline was developed to increase safety when working in and around ammonia refrigeration systems and to mitigate the consequences of accidental releases. This document provides guidance for ensuring that existing emergency action and/or response plans include appropriate personal protective equipment selection, training, and emergency planning and communication associated with these critical tasks.