That’s a very practical question, and you’re right to be cautious. The short answer is: you should be more worried about wood splinters than metal edges, but only if you choose the wrong type of bench for either material.
Let’s break it down.
The Wood Splinter Reality
Traditional, untreated or poorly finished wooden benches are a splinter nightmare. Even if it feels smooth when new, sun, rain, and daily use will crack the surface. A playground bench gets climbed on, scraped by backpacks, and sat on by kids in shorts. Over time, tiny slivers of wood become exposed. These can be painful and sometimes require a tweezers visit from the school nurse.
The Metal Sharp Edge Reality
A well-made metal bench shouldn’t have sharp edges. Modern playground-grade metal benches are rolled, beveled, or capped. The edges are rounded during manufacturing. The bigger risk with metal isn’t sharpness—it’s heat. A metal bench sitting in direct sun can become hot enough to burn a child’s legs. Also, if the metal is powder-coated poorly, it can chip and create a sharp, rusty spot.
The Real World Winner: How to Choose
If I were advising a school, I would say: Avoid both traditional wood and bare metal. Instead, choose one of these three safe options:
1. Recycled Plastic or HDPE (High-Density Polyethylene) Benches – These look like wood, feel like wood, but never splinter. They are the gold standard for playgrounds. They don’t rot, chip, or require painting. No splinters, no sharp edges.
2. Powder-Coated Steel with Rounded Ends – If you must choose metal, look for a bench with full vertical and horizontal edge rounding (all edges radiused to 1/8 inch or more). Insist on marine-grade powder coating. Check that every bolt is recessed or capped. The metal frame should not have any exposed corners that a running child could hit.
3. Southern Yellow Pine with a "No-Splinter" Sealant – If the budget only allows for real wood, you must buy *playground-grade* lumber. This is usually pressure-treated with a child-safe chemical and then sanded with 120-grit or finer paper. Even then, you will need to re-sand and re-seal it every year. It is high maintenance.
The Bottom Line for Your School
Don’t worry about splinters versus edges. Worry about maintenance. An unmaintained wood bench will always splinter. A poorly made metal bench will always develop a sharp burr. A recycled plastic bench is virtually maintenance-free.
For a school playground, I strongly recommend recycled plastic slats over a powder-coated steel frame. This gives you the warm look of wood with zero splinters, and the steel frame gives you durability without sharp edges. Ask the supplier for "radius edges" on all steel components.
You are not overthinking this. Kids are hard on furniture. Choose a bench that is designed specifically for a playground—not a garden bench—and you will sleep well knowing the only thing your students have to worry about is who gets to sit on it first.