It has been the sole means of resupply and the only point of evacuation for migrant workers and hospital patients, who have been carried to safety by ships, tugs and fishing vessels that have dared enter its channel, at risk of facing a gantlet of fire.
On October 10, the Viet Minh were given full control of Hanoi, closing off one point of evacuation for those who wanted out.
Since each evacuee starts from various points in the area, concentration of evacuees on specific roads is unlikely to occur at the early stage of evacuation.
Threats which originate in a context where aid workers are not present may impact where and how aid agencies operate in neighbouring countries to the point of forcing evacuations.
Freon is the traditional primary cryogen used for freezing specimens for freeze-fracture electron microscopy but its use is now discouraged owing to deleterious effects on the ozone layer; the alternatives are to use propane as a primary cryogen (cooled with liquid nitrogen) or nitrogen slush (liquid nitrogen cooled below its boiling point by subjecting to cycles of evacuation).
Beginning in September 2008, all healthcare services, including medications, consultations, and evacuations to hospitals, were exempted from point-of-service user fees.
In the wake of last month's discovery that the extent of Arctic sea ice coverage hit a record low this year, climate scientist Michael Mann told the Guardian that "Island nations that have considered the possibility of evacuation at some point, like Tuvalu, may have to be contending those sort of decisions within the matter of a decade or so".
Many come from the New York City area, where questions have been raised about the adequacy of evacuation plans for the Indian Point plants, 35 miles north of Midtown Manhattan.
In the evacuation model, the required evacuation time was determined mainly by the following factors: distance from the farthest point to the safety exit, personnel evacuation speed, width of evacuation exit, and density of personnel.
Opponents of Indian Point argue that evacuation of residents in a 10-mile radius would take far too long.
