Can a switching power supply kill you?
The thing that is dangerous for the human body is current. While its effect depend on path (though heart or not), duration of the exposition and frequency (in your case DC) in general currents above 1 A are considered deadly.




AC-1 zone: Imperceptible

AC-2 zone: Perceptible

AC-3 zone: Reversible effects: muscular contraction

AC-4 zone: Possibility of irreversible effects

AC-4-1 zone: Up to 5% probability of heart fibrillation

AC-4-2 zone: Up to 50% probability of heart fibrillation

AC-4-3 zone: More than 50% probability of heart fibrillation


Source: https://www.electrical-installation.org/enwiki/Protection_against_electric_shock

On the other hand you have to consider that the human body-resistance is voltage dependent (higher voltages = lower body resistance).Below 25 V it is around 60 kOhm. In general, DC voltages below 120 V are not considered deadly, that’s why you can hold a battery with your hands and no current will flow through you, but if you short circuit a battery you can create high currents indeed.

Long story short: the 24 V output of your power supply won’t kill anybody.