It follows more than a dozen arson incidents at the construction site
Gardai have confirmed a fake bomb was found at the site of the National Children's Hospital in Dublin earlier this week.
Officers were alerted to a suspicious device at the premises on James' Street just before midday on Monday.
The area was cordoned off and bomb disposal experts from the Army were called in.
The device was deemed non-viable and the scene was declared safe just after 5pm.
It follows more than a dozen arson incidents at the construction site over the summer as part of a campaign to disrupt work.

Over 400 Motorists Caught Speeding So Far Today, Including A Driver In Kilcock
Transport Minister In Discussions With Irish Rail About Extending Late-Night Trains Beyond Christmas
Tadhg And Mary Should Be Looking Forward To Christmas, Say Gardai As Fresh Appeal Launched
Bus Shelters Treated As Luxury Rather Than Standard, With 500 Kildare Bus Stops In Need Of Upgrades
Recruitment Announcements Don’t Add Up As Garda Numbers Stagnant In Kildare South, Says Local TD
Court Orders Demolition Of 29 Unauthorised Modular Homes Built By Kildare Developer
Chris Rea, 'Driving Home For Christmas' Singer, Has Died Aged 74
170 People Arrested In Past Week For Driving Under Influence Of Alcohol Or Drugs