NPPS consists of four categories of questions: 1) Supervision
potentials of the playground for the parent or/and care-givers (included four questions about
the presence of a parent or care-giver at the area of the playground during the playing activity,
the capability of visual contact between parents and children during free playing or using part
of the equipment, as well as the existence of a discernible rules-of-behavior panel). 2) Age
appropriate design of the equipment (included six questions about the presence of separate
areas for ages 1-5 and 5-8 years old, the existence of age specific equipment rules, sufficiency
of entrances and exits for the equipment, appropriateness of protective guardrails, design
preventing from climbing outside the equipment and on the supporting). 3) Surface of the
playground (included five questions about appropriateness of the surface of the ground and
the six foot use zone, the depth of loose fill, the covering of concrete footings and foreign
objects absence). 4) Maintenance of the equipment (included eight questions about sufficiency
of the playground equipment. Particularly, the questions referred to any sort of malfunction
that could appear on the equipment, such as broken or missing parts, protruding bolts and
noticeable gaps that could cause an injury, potential accident traps, rust, splinters and cracks
and/or holes).