What is the maximum allowable angle for form work according to standard guidelines?

The maximum allowable angle for formwork is determined by the guidelines for construction practices, particularly focused on ensuring the stability and safety of both the workers and the structure. In this context, the correct choice of Span / 360 indicates that the allowable angle is a relatively conservative measurement, aimed at preventing excessive deformation or instability in the formwork due to environmental variables such as loads, temperature variations, or wind.

Using Span / 360 means that for every length of span, the angle of the formwork is kept to a minimum—resulting in a steeper angle relative to the span. This minimizes the potential for slippage or structural failure during the curing process of the concrete. Lower angles generally provide better support and distribution of weight, which is critical in concrete placements.

The other choices represent less conservative standards that could allow for a broader angle, thus increasing the risk of formwork failure. A larger angle might compromise the stability and safety of the construction, which is why the Span / 360 recommendation is typically preferred in standard guidelines.