13.2 Use Zones

13.2 Use Zones

Domain 3G of the NRPA CPSI blueprint is the tape-measure chapter for the space around the equipment, not the equipment itself. Domain 1O already taught slide exits, swing bays, and rotator rings as performance rows. Domain 3E already put moving equipment toward a corner and kept access components out of slide exits. Domain 3G asks you to name the use zone, measure it, and refuse to shrink the surfacing when an overlap rule does not apply.

The U.S. Consumer Product Safety Commission (CPSC) Public Playground Safety Handbook, Publication 325 (July 2025) defines a use zone as the surface under and around a piece of equipment onto which a child falling from or exiting from the equipment would be expected to land. The same envelope also provides unrestricted circulation around the equipment. That second sentence is why a use zone is not just a fall pit. A caregiver walking a stroller, a child running the perimeter, and the child who jumps off the deck all occupy that band. Protective surfacing that meets ASTM F1292 for the relevant fall height belongs throughout the use zone, not only in the pretty circle under the deck.

Stationary equipment and NRPA 9.2.3 overlap

Stationary equipment — climbers, composites, stand-alone decks, most activity panels that are not swinging or rotating — takes a minimum 72 inches (6 feet) in all directions from the perimeter. That is the default row. Do not invent a 48-inch "small climber" exception, and do not treat the equipment footprint as the use zone.

Adjacent structures may share space only on the published overlap terms. NRPA §9.2.3 (the overlap block on the Table of Dimensions) is the exam-sheet wording:

CPSC's matching narrative is the 6-foot / 9-foot pair Domain 1O already used on climbers: overlap is allowed when adjacent designated play surfaces are 30 inches or lower and the structures are at least 6 feet apart; when either surface is taller than 30 inches, the structures need 9 feet (108 inches) between them. Write the Table's 72 / 108 figures and the 30-inch trigger. A 48-inch deck beside another 48-inch deck is the 108-inch case even if both composites are IPEMA-labeled.

Overlap is a spacing rule between two use zones. It is not permission to omit F1292 surfacing in the remaining envelope, and it is not a free pass to shrink surfacing under swings or slides whose published zones may not overlap.

Equipment rows that overwrite the 72-inch default

Memorize the non-default rows. The exam will hand you a tire, a disc swing, a slide exit, or a standing rocker and wait for the wrong 6-foot circle.

Slide exits are 72 inches for slides 6 feet or shorter, and equal to slide height up to 96 inches for taller slides (Domain 1O / CPSC §5.3.6.5). On a composite, no access component — stair, ramp, climber, or transfer — may sit in that exit zone. Domain 3E already called that a layout conflict. Domain 3G is why: the exit zone is a use zone with a non-overlap rule, not leftover mulch beside the chute.

To-fro (single-axis) swings keep 72 inches from the support structure to the side. The front-and-rear envelope is the 2X formula from Domain 1O; that band does not borrow space from a slide exit or another bay. Rotating swings take a non-overlapping circle of Y + 72 inches, where Y is the vertical distance from the pivot to the top of the seat. Multi-axis swings use the Table's Y + 30 inches row. Swapping those two Y formulas is a scored miss. Sitting rockers and sitting swinging postures stay on the 72-inch row; standing rockers take 84 inches.

Place the machine so the zone still fits

CPSC §2.2.4 is the layout sentence Domain 3G still owns: moving equipment, such as swings and merry-go-rounds, should be located toward a corner, side, or edge of the play area so the large, often non-overlapping zones fit without chewing through the composite or the slide run-out. Slide exits stay in uncongested space. You measure the zone first, then decide whether the equipment is in the wrong place. You do not move the tape because the bay was poured in the middle of the pad.

Surfacing throughout the measured use zone must meet ASTM F1292 for the fall height of that equipment. A 72-inch ring of engineered wood fiber that fades to packed dirt at 50 inches is not a 72-inch use zone. A poured-in-place patch that stops at the drip line of the deck leaves the landing area unprotected. Overlap between two short stationary climbers does not let you pull the rubber back from under a tire swing or shorten a 96-inch slide exit to 48 inches "because the zones touch."

Walk Domain 3G in this order:

1. Name the equipment family (stationary, slide exit, to-fro, rotating, multi-axis, sitting rocker, standing rocker).
2. Tape the published zone — 72 inches default, 72–96 inches at a slide exit, 72 inches at a to-fro support, Y + 72 or Y + 30 on the swing rows, 84 inches on a standing rocker.
3. Apply NRPA 9.2.3 only where overlap is actually allowed (30-inch designated-play-surface trigger; 72 / 108).
4. Confirm no access component sits in a slide exit zone and that non-overlapping swing and slide zones were not cut to fit.
5. Confirm F1292 surfacing covers the entire remaining zone at this fall height.
6. If a moving-equipment zone will not fit, the machine belongs at a corner, side, or edge — you do not shrink the zone.

That is Domain 3G: definition, 72-inch stationary default, 9.2.3 overlap, equipment-specific rows, and surfacing that follows the tape rather than the catalog photo.