What type of ladder must be provided when manhole openings cannot be placed safely?

Providing a fixed ladder is necessary when manhole openings cannot be safely accessed from ground level or when there is an elevated work area. A fixed ladder offers permanent access to various heights and stability that portable or other types of ladders may not provide. Fixed ladders are securely attached to a structure, which minimizes the risk of movement or instability that can be dangerous when working near hazardous openings, such as manhole covers.

In contrast, portable, extension, and attic ladders may not provide the same level of safety or structural reliability needed in these scenarios. Portable ladders can be unstable if not properly secured, extension ladders can be cumbersome and may not fit the height requirements or safe angles, and attic ladders are typically designed for infrequent use in residential settings rather than for work in utilities or public safety environments. Therefore, the requirement for a fixed ladder ensures continued access while maintaining the highest safety standards.