(1) You must provide an overflow pipe on dip tanks that:
(a) Hold more than one hundred fifty gallons of liquid; or
(b) Have more than ten square feet of liquid surface area.
(2) You must make sure the overflow pipe is:
(a) Properly trapped;
(b) Able to prevent the dip tank from overflowing;
(c) Three inches or more (7.6 cm) in diameter;
(d) Discharged to a safe location.
Note: | Discharged to a safe location could be a: |
| 1. Safe location outside the building; or |
| 2. Closed, properly vented salvage tank or tanks that can hold more than the dip tank. |
(3) You must make sure the bottom of the overflow pipe is at least six inches (15.2 cm) below the top of the tank.
Note: | The overflow pipe should be large enough to remove water applied to the liquid surface of the dip tank from automatic sprinklers or other sources in the event of fire. Smaller dip tanks should be equipped with overflow pipes, if practical. |
[Statutory Authority: RCW
49.17.010,
49.17.040,
49.17.050, and
49.17.060. WSR 17-18-075, § 296-835-12010, filed 9/5/17, effective 10/6/17. Statutory Authority: RCW
49.17.010, [49.17].040, and [49.17].050. WSR 02-15-102, § 296-835-12010, filed 7/17/02, effective 10/1/02.]