Rescue will workers will start hoisting 33 miners trapped underground in Chile to the surface soon.
One by one, the men will be raised in special capsules developed by the Chilean navy, winched up through a hole nearly 2050ft long and not much wider than a man's shoulders.
The country's mining minister Laurence Golborne said: "This test has been very successful. We set some TV cameras inside the Phoenix we could we would watch how the hole behaved during the process of movement of the cage and we could see that there was no stones, neither dust that was liberated during this process."
As relatives wait anxiously and journalists swarm the mine in the Atacama desert of northern Chile, Mr Golborne explained the various stages of assessing the medical condition of each of the trapped miners after they are pulled from the narrow hole.
Officials, worried about panic attacks, will bring up those who are physically and mentally strongest first to see how the men react to the claustrophobic journey.
Reports say the miners are in remarkably good health, although some have developed skin infections.
The government has brought in experts from Nasa to help the men keep physically and mentally fit during the ordeal.
