Engineered design of scaffold is confirmed when over 120’ in height or if any wrapping is used (could create a sail). 

Okland

Subpart L (33, 34) pg. 39

33. All scaffolds wrapped or enclosed with fabric, plastic or similar wrap shall be designed by a qualified person and shall be constructed per that design. Design drawing shall be Project and application specific. Documentation of the design shall be submitted to the Okland Superintendent prior to the construction of the scaffold/platform.

34. Okland’s Corporate Risk Management and/or Safety Department, may require, due to the elevated level of risk a scaffold poses, that the scaffold or certain components of the scaffold (e.g. scaffold wrap) be designed/engineered by a registered professional engineer. Such designs may include but not be limited to the scaffolding and scaffold wrap anchoring methods and requirements.