Final answer:
The recommended height range for a proper guardrail system is around 42 to 48 inches.
Step-by-step explanation:
The recommended height range for a proper guardrail system from the walking/working surface, with an acceptable tolerance of approximately plus or minus 3 inches, is typically around 42 to 48 inches. This height range is commonly followed to ensure the safety of individuals by preventing falls or accidents. It provides a barrier that is high enough to prevent people from accidentally going over the railing, but low enough to allow them to see and access the walking/working surface.