Misbehaving adults and dodgy operators are being blamed for an alarming increase in the number of injuries on bouncy castles.
Injuries range from bruises, sprains and cuts to lost teeth, broken arms and in some instances, serious head injuries when things go wrong. However, those in the industry say poor adult behaviour and irresponsible operators are to blame.
This year, ACC has paid out almost $74,300 for 382 injuries relating to bouncy castles - a dramatic increase on the $1000 paid out 10 years ago.
Since then figures have steadily increased, averaging at more than 300 claims every year, costing taxpayers more than $600,000 in the last five years.
The figures cover all incidents where 'bouncy castle' was listed in the accident description on claim forms.
Those in the industry say irresponsible adults are often mixing booze and bouncing, causing damage to themselves, children and equipment.
Owner of Christchurch's Go-Jump, Matt Dalley, doesn't let adults use his bouncy castles because of potential problems: "It's not worth it".
"People have a drink, they could fight on there or wrestle. You could really do yourself some damage," he said.
"It often happens as soon as we're out the gates; you get adults jumping on the thing, knocking kids over," added the owner of Auckland's Smile Inflatables, Stacy Cooney, who hires castles for a range of events including, kids' parties, 21sts, corporate events, bar mitzvahs and Christmas parties.
The company follows strict safety procedures to make sure the castles are well-secured to the ground and issues rules for users to follow, but it is impossible to prevent every potential accident, said Mr Cooney.
"We've come back to parties and they've pulled the pins out and moved the thing."
Adults' failure to supervise their children properly also leads to injuries. One operator said a client's child had knocked out their teeth after falling off a bouncy castle, and another child broke his arm.
Emergency department staff at Hawke's Bay Hospital have treated three people with bouncy castle-related injuries in the last six months, a spokeswoman confirmed.
Dodgy operators are also having an impact on the level of injuries, say those in the industry.
In particular, they are aware of instances were castles had not been correctly secured to the ground, which created the potential for serious injuries.
Last week a staff Christmas party in Whangarei ended in tears when four children were taken to hospital after strong winds blew a bouncy castle along the ground.
Three children aged four, five and six were taken to hospital with minor injuries after a gust of wind picked up the castle and dragged it about 20 metres.
The inflatable had been secured to the ground with electric fence stakes, said someone at the party.
The New Zealand statistics largely mirror those found in an American Academy of Pediatrics study, which found the number of children with inflatable 'bouncer'-related injuries treated in emergency departments had increased 15-fold between 1995 and 2010.
The increase was particularly rapid in recent years, reaching an average of 31 children injured each day in 2010, and highlighted the need for guidelines for safer bouncer usage and improvements in bouncer design, said the authors.
Most of the injuries suffered were fractures, strains and sprains.
In reported accidents in America and the UK, children have suffered serious head injuries after falling off bouncy castles.