Lasers are classified into four broad areas depending on the potential for causing biological damage.

In recent years, scientists have raised their estimate of the amount of biological damage caused by neutrons.

However, knowing the activity tells us very little about the possible biological damage caused.

Radiation of high LET can deposit most of its energy within a cell and this results in greater biological damage.

This relates the absorbed dose in human tissue to the effective biological damage of the radiation.

Neutrons readily pass through most material, but interact enough to cause biological damage.

This isn't the type of damage that you go to the doctor for, but normal biological damage called catabolism.

Identifying effective countermeasures that reduce the risk of biological damage is still a long term goal for space researchers.

Benthic sediment buildup causes biological damage and reduces aquatic biodiversity.

"The indications are there is biological damage," he said.