As has been stated, aisles must be a certain width (wider than the load or truck - whichever is wider) and considerations for two way traffic. This is to eliminate a load having to be elevated to get around anything and to avoid hitting anything when the load is low to the floor/ground.
All loads are to be secure to avoid anything falling off.
I see by your post, you're in Canada. A good example is to look at the Canada Labour Code and they also identify pedestrian walkways and how wide they should be as well.
In Ontario many years ago, DOT came up with a poster suggesting a 3M Circle of Safety. In the real world this is not always happen so lift trucks must stay as far away from pedestrians as possible. We just had another fatality down our way, a pedestrian being crushed by a lift truck. In fact, the last 3 fatalities down this way have been pedestrians crushed between a lift truck and another solid object. OSHA did a study a number of years ago on lift truck accidents and their statistic is suggesting 36% of the lift truck fatalities are a pedestrian being crushed by a lift truck.