The European Union has issued a blacklist banning 92 airlines from operating in the region, saying they fail to meet international standards.
The EU wants to avoid a serious loss of life in a member nation
Most of the airlines are based in Africa, including 50 carriers from the Democratic Republic of Congo, 14 from Sierra Leone and seven from Swaziland.
The list is available online and will be updated at least every three months.
The move was proposed last year after a summer in which more than 500 people died in plane crashes worldwide.
From now on, companies banned in one member state will be banned in the whole EU, plus Norway and Switzerland. Airlines can apply to be taken off the list.
"The European Union now has a coherent approach to banning airlines," said Jacques Barrot, the EU's transport commissioner.
"This blacklist will keep dubious airlines out of Europe. It will also make sure that all airlines operating in Europe's sky meet the highest safety standards."
Mr Barrot said that although many of the carriers on the list did not currently fly to Europe, the list would "pre-empt" problems.
He said it was difficult to say how many of the airlines had flown in Europe or used European airports.
The EU says bans and operating restrictions are based on evidence of airlines violating certain criteria, such as the use of poorly-maintained, antiquated or obsolete aircraft.
The list of 92 firms which face a complete ban and three facing operational restrictions was compiled from recommendations from the 25 members of the EU.
The blacklist includes cargo and passenger airlines.
Thailand's Phuket Airlines is on the list, as well as carriers from Kazakhstan, Afghanistan and North Korea.
Travel agents in Europe will be expected to inform customers the identity of an airline they are flying on, and will have to inform them if the airline is banned in Europe.
The EU says the blacklist will encourage airlines operating in Europe to comply fully with safety standards and will dissuade unscrupulous airlines from starting up services in Europe.