Since mid September 2004, every inflatable manufactured or imported into the UK should have a uniquely numbered tag. This tag means that it has been tested against stringent standards and has passed this initial test.
In addition inflatables are required to undergo an annual test, similar to an MOT. Untagged units will be tagged as and when they are presented for annual testing. This means that if you are hiring or buying an inflatable you should be able to look for and find the tag number actually on the unit.
If there is no tag then it has not been tested under the PIPA scheme
You can also find the current test status of any tagged inflatable from this site. Simply enter the tag number on this page to see when the last annual test was carried out and when the next test is due.