Advantages
- Low initial cost.
- Ease of installation.
- Good drainage
- Less abrasive than sand.
- Less attractive to cats and dogs (compared to sand).
- Attractive appearance.
- Readily available.

Disadvantages
The following conditions may reduce cushioning potential:
- Rainy weather, high humidity, freezing temperatures.
- With normal use over time, combines with dirt and other foreign materials.
- Over time, decomposes, is pulverized, and compacts requiring replenishment.
- Depth may be reduced by displacement due to children's activities or by material being blown by wind.
- Can be blown or thrown into children's eyes.
- Subject to microbial growth when wet.
- Conceals animal excrement and trash (e.g., broken glass, nails, pencils, and other sharp objects that can cause cut and puncture wounds).
- Spreads easily outside of containment area.
- Can be flammable.
- Subject to theft by neighborhood residents for use as mulch.

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Inorganic Loose Material
sand and gravel

Installation/Maintenance
- Should not be installed over existing hard surfaces (e.g., asphalt, concrete).
- Method of containment needed (e.g., retaining barrier, excavated pit).
- Good drainage required underneath material.
- Requires periodic renewal or replacement and continuous maintenance (e.g. leveling, grading, sifting, raking) to maintain appropriate depth and remove foreign matter.
- Compacted sand should periodically be turned over, loosened, and cleaned.
- Gravel may require periodic break up and removal of hard pan.

Advantages
- Low initial cost.
- Ease of installation.
- Does not pulverize.
- Not ideal for microbial growth.
- Nonflammable.
- Materials are readily available.
- Not susceptible to vandalism except by contamination.
- Gravel is less attractive to animals than sand.

Disadvantages
The following conditions may reduce cushioning potential:
Rainy weather, high humidity, freezing temperatures.
- With normal use, combines with dirt and other foreign materials.
- Depth may be reduced due to displacement by children's activities and sand may be blown by wind.
- May be blown or thrown into children's eyes.
- May be swallowed.
- Conceals animal excrement and trash (e.g., broken glass, nails, pencils, and other sharp objects that can cause cut and puncture wounds).

Sand
- Spreads easily outside of containment area.
- Small particles bind together and become less cushioning when wet; when thoroughly wet, sand reacts as a rigid material.
- May be tracked out of play area on shoes; abrasive to floor surfaces when tracked indoors; abrasive to plastic materials.
- Adheres to clothing.
- Susceptible to fouling by animals.

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Inorganic Loose Material
shredded tires

Installation/Maintenance
- Should not be installed over existing hard surfaces (e.g., asphalt, concrete).
- Method of containment needed (e.g., retaining barrier, excavated pit).
- Good drainage required underneath material.
- Requires continuous maintenance (e.g., leveling, grading, sifting, raking) to maintain appropriate depth and remove foreign matter.

Advantages
- Ease of installation.
- Has superior shock absorbing capability.
- Is not abrasive.
- Less likely to compact than other loose-fill materials.
- Not ideal for microbial growth.
- Does not deteriorate over time.

Disadvantages
- Is flammable.
- Unless treated, may cause soiling of clothing.
- May contain steel wires from steel belted tires. Note: Some manufacturers provide a wire-free guarantee.
- Depth may be reduced due to displacement by children's activities.
- May be swallowed.

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Unitary Synthetic Materials
rubber or rubber over foam mats or tiles, poured-in-place urethane and rubber compositions

Installation/Maintenance
Some unitary materials can be laid directly on hard surfaces such as asphalt or concrete. Others may require expert under-surface preparation and installation by the manufacturer or a local contractor. Materials generally require no additional means of containment. Once installed, the materials require minimal maintenance.

Advantages
- Low maintenance.
- Easy to clean.
- Consistent shock absorbency.
- Material not displaced by children during play activities.
- Generally low life cycle costs.
- Good footing (depends on surface texture.)
- Harbor few foreign objects.
- Generally no retaining edges needed.
- Is accessible to the handicapped.

Disadvantages
- Initial cost relatively high.
- Undersurfacing may be critical for thinner materials.
- Often must be used on almost level uniform surfaces.
- May be flammable.
- Subject to vandalism (e.g., ignited, defaced, cut).
- Full rubber tiles may curl up and cause tripping.
- Some designs susceptible to frost damage.