The Department of Foreign Affairs strongly recommends that comprehensive travel insurance including medical insurance, is obtained before travelling to the United States of America (USA),as the cost of medical care in the USA can be very high. Travellers should note that the Irish government does not provide funds for emergency medical repatriation or for repatriation of remains.
Please note that the Customs and Border Protection Agency has warned of possible increased wait times at major U.S. international airports, especially during the summer peak season, due to the effects of sequestration budget cuts. It warns of waits of up to 50 percent or more, with peak waits of up to four hours at the busiest airports. Increased processing times at airports — including both CBP operations and Transportation Security Administration screening – may make it more difficult for travelers to make tight connecting flights. Further information is here.
The Yosemite National Park has a non-emergency phone line (+1-209-372-0822) for all questions and concerns related to Hantavirus in Yosemite National Park. The park is also updating its website daily to reflect current information on confirmed cases and any additional important information. The information can be found at http://www.nps.gov/yose/planyourvisit/hantafaq.htm.
The Centers for Disease Control and Prevention (CDC) has a hotline number (+1-404-639-1510) and information about HPS on their Hantavirus website.
Irish citizens travelling or living overseas, outside the Common Travel Area, (Ireland/Great Britain) are encouraged to register their contact details with the Department of Foreign Affairs.
Registration is voluntary. It is a facility available to all Irish citizens and is intended for use by people travelling on holidays, and also for business travellers and Irish citizens living overseas. Irish citizens can register here.
Entering the US under the Visa Waiver Programme
As from July 1st 2009, nationals or citizens of VWP (Visa Waiver
Programme) countries have not been permitted to enter the
United States under the VWP using emergency and temporary passports
issued after 26 October 2006, unless those passports have an
integrated computer chip holding the same information printed on
the passport bio-page (“e-passport”).
Irish Emergency Passports do not have an integrated computer chip and therefore can only be used for entry to the United States if the traveller has been issued with a Visa.
Electronic System for Travel Authorization (ESTA)
ESTA is an electronic registration system requiring travellers who are part of the Visa Waiver Program (VWP) to register in advance of travelling to the USA. Mandatory registration has come into force since 12 January 2009.
Visa Waiver travellers should register through the Department of Homeland Security website at the following address: https://esta.cbp.dhs.gov. Travellers from Visa Waiver Program countries are required to pay a fee when applying for an Electronic System for Travel Authorization (ESTA). The fee is currently $14.
Registration may be done by third parties e.g. travel agencies.
ESTA applications may be submitted at any time prior to travel, and once approved, generally will be valid for up to two years or until the applicant's passport expires, whichever comes first. Authorisations will be valid for multiple entries into the U.S. The Department of Homeland Security recommends that ESTA applications be submitted at least 72 hours in advance of travel.
An applicant who does not receive authorisation to travel will need to go to their nearest U.S. Diplomatic or Consular Mission and apply for a visa.
An ESTA approval does not determine admissibility into the United States. The final decision for entry to the United States rests with US immigration authorities at the port of entry.
The ESTA programme does not apply to Irish citizens who are holders of a visa for the United States.
For more information on ESTA, please visit http://www.cbp.gov/ESTA
Visa free travel to the U.S. under the Visa Waiver Program (VWP).
Since 26 October 2004, all Irish passport holders visiting the United States require an individual machine readable passport to avail of the U.S. Visa Waiver Programme. Otherwise they must obtain a visa, in advance, from their nearest U.S. Diplomatic or Consular Mission.
Under the U.S. Visa Waiver Programme, passport holders from 27 countries, including Ireland, may enter the U.S. without a visa for tourism or business purposes for a maximum period of 90 days.
A machine readable passport is a passport in which the holder's details have been printed on the datapage which also contains the holder's photograph. A passport where the holder's details have been handwritten is not a machine readable passport.
Children, including infants, who are endorsed on a parent's passport must have an individual machine readable passport or else obtain a visa in the parent's passport.
Passport Validity
In most cases, to enter the US, you must have a passport that is valid for at least six months after the date you enter. However, Ireland has an agreement with the US that allows you to enter on a current passport up to the actual date of expiration. An Irish passport need remain valid only for the duration of the holder's stay in the United States.
However, if you are traveling visa-free on the Visa Waiver Program (VWP) and your passport is valid for less than 90 days, you will be admitted only until the date on which the passport expires. If the passport is not valid for the duration of your stay, you will be required to apply for a new passport from your nearest Irish Embassy or Consulate while in the U.S.
Further details on entry requirements are available on the U.S. Embassy website.
Those travelling on J1 visas may wish to check the Travel Advice for J1 Students.
SAFETY & SECURITY
The US Government remains concerned about continued threats. Since the terrorist attacks on 11 September 2001, the US government has issued a number of warnings of potential further terrorist attacks in the US. The US domestic threat level stands at "elevated" (yellow). The US Government is maintaining heightened security, especially at airports. You should continue to expect stringent security checks at airports, transport stations and other public buildings.
CLIMATE
The hurricane season runs from 1 June to 30 November, and can affect the whole of the southern USA. Please check the National Hurricane Centre website for more details.
Irish citizens who intend to travel to these areas should monitor information on the US National Hurricane Centre website National Hurricane Center. Irish citizens are advised to monitor local weather reports on www.weather.gov and can also access local information on the Federal Emergency Management Agency (FEMA) website at http://www.fema.gov/ and at http://blog.fema.gov/
FEMA's website also contains information about how to prepare for
extreme weather conditions and what to do if you are told to
evacuate. It also provides a useful list of disaster supplies that
will help if you live in an area affected by storms and hurricanes.
Irish citizens, visiting and residing in the United States, are advised to follow the advice of the US Centre for Disease Control available at http://www.cdc.gov/
DIPLOMATIC AND CONSULAR MISSIONS IN THE USA
The Irish Embassy in Washington DC and the Irish Consulates in Atlanta, Boston, Chicago, New York and San Francisco offer consular assistance to Irish citizens. Contact details for all Irish Missions in USA are available here.

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Please call the Department of Foreign Affairs and Trade in Dublin at +3531 4082000 if you have concerns about Irish relatives or friends.
The Boston authorities helpline number is 001 6176354500.