Precaution shall be exercised at all times for the protection of persons (including employees) and property. All safety provisions of applicable state laws, standards and rules and regulations and City ordinances, including building and construction codes as hereafter revised and/or amended, shall be observed. [Ord. 1021 § 11, 1961; Code 1970 § 12.24.140; Code 1954 § 4-5.56.]