#Diving - An Irishman who set a world record for long-distance SCUBA diving is preparing to double that incredible feat.

Christopher Healy set the Guinness World Record for the fastest SCUBA dive over a distance of 10km in October 2011 in an effort to raise funds for the Share a Dream Foundation, which raised the spirits of his son Stephen when he was diagnosed with Non-Hodgkin's Lymphoma.

The experienced diving instructor - who runs the Atlantic Diving School in Co Clare - followed a long line of Irish divers such as Declan Devine, Sean McGahern and Paul Devane who've either smashed or attempted to smash records in the field.

And Healy has since written a book, The 10K Record, about the highs and lows of his journey to breaking the record.

But this weekend he aims to double that effort - and raise more funds for Share a Dream and Temple Street Children's Hospital - by SCUBA diving an unbroken 20km route in Lough Derg.

Staring at Mountshannon Harbour at 3am this Sunday 7 July, Healy will travel underwater towards Scariff and back via Scilly Island to Killaloe, aiming to arrive around 3pm.

He will be accompanied along the way by a small flotilla of support boats to replace his air supply and record his journey for verification.

For more about Healy's 20km diving challenge and how you can donate, visit the Facebook page HERE.