The standard applies to all types of water. The detection limit depends on the device used; In general, aluminum contents can be determined from 0.1 mg/l. For levels lower than 0.1 mg/l, an extraction method is recommended, see 10.
NEN 6439-1986 history
1982NEN 6439-1986 Water - Determination of aluminium content by atomic absorption spectrometry (flame technique)