Lime in the Playground
Why Lime Should Not Be Used Under Playgrounds
Introduction
Playgrounds are essential spaces for childhood development, offering children opportunities for physical activity, social interaction, and imaginative play. To ensure the safety and well-being of children, it is critical that playground surfaces are properly designed and maintained. Traditionally, materials like sand, wood chips, rubber, and engineered wood fiber have been used under playgrounds to absorb shock and provide a safe, comfortable environment for play. However, there is increasing concern about the use of lime—whether agricultural or hydrated lime—as a material beneath playground surfaces.
This white paper outlines the reasons why lime should not be used under playgrounds, examining its potential health risks, environmental impact, and limitations as a playground surface material.
1. Health and Safety Concerns
1.1 Skin Irritation and Burns
Lime, particularly in its hydrated form, is highly caustic. When it comes into contact with skin, it can cause irritation, burns, and severe discomfort. For children who are likely to be in direct contact with the surface—falling, crawling, or playing close to the ground—there is an elevated risk of injury. Even small amounts of lime dust or particles can be harmful if they come into contact with sensitive skin. These burns can range from mild to severe and may require medical attention. In humid and moist climates, even under layers of other surfacing, this material can bleed through to upper layers. In periods of dry conditions, particulate material through vibration and subsurface erosion, find its way to contact bearing surfacing and and in the adjacency of the playground.
1.2 Respiratory Issues
Lime can release dust into the air, which poses a significant respiratory risk, especially for children who are breathing it in while playing. Inhalation of lime dust may irritate the respiratory system, leading to coughing, shortness of breath, or even long-term health complications. In severe cases, it can cause chemical pneumonitis (inflammation of the lungs), which requires immediate medical care. Even in subsurface layers, conditions may be present to hydrate and dehydrate and allow for surface level and grade exposure.
1.3 Chemical Exposure
Lime, when exposed to moisture, can undergo a chemical reaction that produces heat, potentially exacerbating the risk of burns. Additionally, prolonged exposure to lime in the soil can lead to the leaching of chemicals into the ground, affecting the surrounding environment and raising concerns about potential contamination of the water table.
2. Environmental Impact
2.1 Soil Disruption
Lime is often used in soil treatment to increase pH levels and reduce acidity. While this may be beneficial in agricultural contexts, applying lime under a playground can disrupt the natural pH balance of the soil, which is crucial for maintaining local biodiversity. Many plants and insects depend on a stable pH level in the soil, and the introduction of lime can harm these organisms, creating long-term ecological imbalances in the playground area.
2.2 Impact on Surrounding Vegetation
The application of lime can have adverse effects on the surrounding plant life. The raised pH levels resulting from lime can alter the growth conditions of vegetation, leading to stunted growth or even the death of nearby plants. This not only reduces the aesthetic value of the playground but can also affect local wildlife that depends on those plants for food or shelter.
2.3 Water Contamination
When lime interacts with water, it has the potential to create run-off that may carry residual chemicals. This run-off can contaminate nearby water sources, affecting the ecosystem and possibly harming aquatic life. Given that children often play near or around water features on playgrounds, this is a concerning risk.
3. Durability and Practical Concerns
3.1 Erosion and Maintenance Challenges
Lime is prone to erosion, especially in high-traffic areas like playgrounds. This erosion can lead to uneven surfaces, creating tripping hazards and reducing the overall safety of the playground. Lime also requires significant ongoing maintenance, as it can wash away with rain, necessitating frequent reapplication to maintain its intended effect. This adds to the cost and labor required to maintain the playground over time. Beneath layers of playground surfacing and material, this becomes more destructive through allowance of subsurface conditions that may not be visible to inspection prior to disruption of the playground surfacing itself.
4. Conclusion
The use of lime under playgrounds introduces a number of significant health, safety, environmental, and maintenance concerns. From skin irritation and respiratory risks to the negative impact on local ecosystems, lime proves to be an inadequate subsurface material for playgrounds.
To ensure that playgrounds remain safe, enjoyable spaces for children, it is critical to avoid using lime and instead choose materials that are specifically designed to promote the health and well-being of children, the surrounding environment, and the community as a whole.
References
- U.S. Environmental Protection Agency (EPA). "Hydrated Lime." Retrieved from www.epa.gov.
- Centers for Disease Control and Prevention (CDC). "Respiratory Protection and Dust." Retrieved from www.cdc.gov.
- Playground Safety Guidelines. ASTM International. "ASTM F1292 - Standard Specification for Impact Attenuation of Surface Systems Under and Around Playground Equipment."