CAUTION--Heated mixtures of HCIO4. and organic matter may explode violently. Avoid this hazard by solul taking the following precautions:
(a) Do not add HClO4 to a hot solution that may contain organic matter.
(b) Always initiate digestion of samples containing organic matter with HNO3. Complete digestion using the mixture of HNO3 and HClO4.
(c) Do not fume with HClO4 in ordinary hoods. Use hoods especially constructed for HCIO4, fuming or a glass fume eradicator connected to a water pump.
(d) Never let samples being digested with HClO4 evaporate to dryness.