The Aeroshell book confirms the info given by the two posters above - and not much else.
Jet A-1
Jet A-1 is a kerosine grade of fuel suitable for most turbine engined aircraft.
It has a flash point minimum of 38°C (100°F) and a freeze point maximum of –47°C. It is widely available outside the U.S.A. The main specifications for Jet A-1 grade (see below) are the UK specification DEF STAN 91-91 (Jet A-1) NATO code F-35, (formerly DERD 2494) and the ASTM specification D 1655 (Jet A-1).
Although developed basically as a military jet fuel, D.Eng RD 2494, issued by the Ministry of Defence, was adopted as the standard UK civil jet fuel. It is now renamed as DEF STAN 91-91 and defines the requirements for a kerosine type fuel (Jet A-1 grade) having a maximum freeze point of – 47°C.
Jet A-1 according to the DEF STAN 91-91 specification is very similar to Jet A-1 defined by the ASTM D 1655 except for a small number of areas where DEF STAN 91-91 is more stringent.
Jet A
Jet A is a kerosine grade fuel, normally only available in the U.S.A. It has
the same flash point as Jet A-1 but a higher freeze point maximum (–40°C).
It is supplied against the ASTM D 1655 (Jet A) specification. Jet A is used within the United States by domestic and international airlines.