This document discusses ergonomics in the construction industry. It states that back injuries from improper lifting and positioning cost an average of $30,000 per case, and are a major cost for construction companies. It also notes that injury rates for construction workers are more than twice the general industry rate. The document outlines how ergonomics aims to reduce injuries by fitting the task to the worker rather than forcing adaptations. It discusses common injuries from repetitive motions and improper postures, and lists principles for safer tool use, workstation design, and materials handling to help prevent cumulative trauma disorders.