Fork and other similar types of lift trucks shall be operated with the-
(a) Upright tilted back to steady and secure the load;
(b) Load in the upgrade position when ascending or descending grades in excess of 10 percent;
(c) Load not raised or lowered enroute except for minor adjustments; and
(d) Load-engaging device downgrade when traveling unloaded on all grades.
053-2 Wyo. Code R. § 56.16016