The following figures are a graphic summary of the requirements contained in Part N for excavations 20 feet or less in depth. Protective systems for use in excavations more than 20 feet in depth must be designed by a registered professional engineer in accordance with WAC 296-155-657(2) and (3).
FIGURE N-27 - PRELIMINARY DECISIONS |
FIGURE N-28 - SLOPING OPTIONS |
FIGURE N-29 - SHORING AND SHIELDING OPTIONS |
Wash. Admin. Code § 296-155-66411
Statutory Authority: RCW 49.17.010, [49.17].040,[49.17].050 . 02-12-098, § 296-155-66411, filed 6/5/02, effective 8/1/02. Statutory Authority: Chapter 49.17 RCW and RCW 49.17.040, [49.17].050 and [49.17].060. 92-22-067 (Order 92-06), § 296-155-66411, filed 10/30/92, effective 12/8/92.