"This document applies to safety observers or spotters involved with the use of outdoor laser systems. It may be used in conjunction with SAE Aerospace Standard (AS4970) ""Human Factors Considerations for Outdoor Laser Operations in the Navigable Airspace."" Additional control measures may be applicable and are listed in ANSI Z136.6. Purpose The purpose of this document is to provide guidance to proprietors for the optimal use of safety observers during operation of a laser system. It also recommends the minimum requirements for a safety observer."