Units of radiation

rem: geiska (GEISlaSKAmmtseining)

sievert: sívörðungur (The surname Sievert derives from the Germanic Sigward (Icelandic: Sigvörður). The collective name of family or followers of this individual would be Sigvörðungar, the singular of which could be used as the surname of an individual family member. I omitted the g in Sig- for two reasons: to make the word more sound-similar with Sievert and because there is a tendency of omitting the latter g of the first lement in a name when the second element begins with 'v-'. An example of this is the Old Icelandic stívarður (English stewart, from stigvörður, see orðsifjabók). The loss of the 'g' in 'sig' has happened in the family name Sievert as well. For that reason, I prefer the construction Sívörðungur instead of Sigvörðungur)

grey: greyingur (Named after Louis Harold Gray). The family name Gray is a toponymical surname and goes back to the place-name Gray in France. The logical adaptation of the family name is Grey + -ingur: Greyingur, which can be used as the name of the unit. )

becquerel: bekkrellingur. Named after Henri Becquerel. The surname Becquerel is mostly found in the French region called 'La Manche" and has the meaning of "little river, brook", the first element becq being of German origin (Icelandic bekkur). The second element is the diminutive suffixe -elle, which phonetically corresponds to -lingur in Icelandic. So the name would be bekklingur. If this sounds to radically an adaptation, the more phonetical and less etymological solution Bekkrellingur is a second option.
http://www.geneanet.org/genealogie/fr/becquerelle.html

curie: kýringur (The surname Curie is found in the French region of 'le doubs' en in 'Haute-Saône' and is a gallicized form of the French-Provençal toponym Curia, Curiaz, the etymology of which is uncertain. The name of the family is icelandicized by adding -ingur to the stem Kurj-.)

rutherford (1 million becquerel): hryðurfurða, myrjundbekkrellingur (= mega-bequerel, myría= 10.000 units with adiition of the suffix -und (as in þúsund, thousand, from þúshundrað) = million. As a suffix mýrjund- can be use to denote the metrical prefix mega-. )

röntgen: röndkin (see http://extremeicelandic.blogspot.com/2011/11/icelandic-equivalent-of-german-surname.html )

rad: eyrisgreyingur (= centigrey, the prefix eyris- (genitive of eyrir, the hundredth part of the Icelandic currency unit, the króna) is used here to designate the metrical prefix centi- (a hundredth part of a unit)