What is the required minimum distance to a laser projector to do a safe laser show?

There is no general value available to determine the actual necessary distance. There are many factors relevant for the actual determination. Please see only a few:

Scan speed, point rate, scanned pattern, beam divergence, output power of the laser projector, beam diametre at aperture, etc.

Internationally the IEC 60825-1 Laser Safety Regulation applies.
It defines the power of laser class 2 in public area as safe for laser shows.
If people can walk underneath the mounted laser system, minimum mounting height is 3m (in Germany: 2,7m). Please respect the actual immission in public area to not exceed laser class 3R.!

You may use laser class 4 projectors to do audience scanning shows, as long as the class 2 value is respected in the public area. Please respect your local legal regulations.

Examples for safe laser class 4 lasershows:

Distributed brands:

Distributed Brand LaserworldDistributed Brand tarmdistributed brand Ray Technologies
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