When is it too windy or wet to use a jumping castle?

Wind is the single biggest danger with any inflatable — the serious accidents you read about are almost always a castle that lifted or blew away. The limits are simple and worth knowing whether you’re hosting a party or running a rental.

The wind limit

Under the inflatable safety standard (EN 14960, adopted in South Africa as SANS 54960), no inflatable should be used in winds above 38 km/h (24 mph) — that’s Force 5 on the Beaufort scale, the point where small trees in leaf start to sway. Some units have a lower limit, so always check the manufacturer’s manual too.

• How to judge it: if small trees are swaying, umbrellas are hard to hold, or the castle’s walls and edges are starting to lift, you’re at or over the limit. A cheap handheld wind meter (anemometer) or a weather app takes out the guesswork.
• Anchoring is not a substitute. Use every anchor point, every time — but pegs and sandbags don’t make it safe to run above the wind limit. If it’s too windy, deflate.
• When in doubt, get everyone off and deflate. It takes seconds and it’s never the wrong call.

Rain and storms

• Light rain: the surface turns slippery fast — stop the bouncing, it becomes a slip-and-fall hazard, and water starts to pool.
• The blower must stay dry. It’s an electrical appliance running the whole time; keep it sheltered and never let it sit in water.
• Heavy rain or a storm: get everyone off, switch off and deflate, and pack up. Dry the castle fully before storing it or you’ll get mould (see cleaning and storage).
• Lightning: everyone off immediately and unplug — don’t wait.

Extreme heat

In full South African summer sun, dark vinyl gets hot enough to burn bare feet, and kids overheat quickly. Set up in shade where you can, provide water, and consider a unit with a roof. Check the surface temperature before little ones climb on.

For operators

Put a clear weather clause in your hire agreement giving you the right to deflate or cancel in unsafe conditions, and don’t let a client pressure you into running in high wind. And have a plan for losing power mid-party — see load shedding and your blower.