This publication provides guidance on best practice for confined space entry. It details appropriate PPE, safe entry policies and procedures, general hazards and atmosphere testing. It also includes survey preparation advice, such as approaches to tank cleaning and lighting.

A 96 page logbook for recording compass and gyro errors. It includes variation charts, as well as full colour sky at night views of the main constellations, with navigable stars highlighted.

Their need, role, design and operational features