Audience scanning tips

Audience scanning shows are regulated in many countries, states/provinces and localities. See this page for a list of countries.

In the United States, a reviewed and approved "variance" from the Food and Drug Administration is required in order to do any laser show over 5 mW. Shows with audience scanning have additional requirements in the variance. No one in the U.S. should do an audience scanning show without an approved variance specifically allowing the audience scanning techniques and procedures. More information on U.S. laws is here.

Audience scanning is under increased scrutiny. There were incidents in 2008 and 2009 where injuries were claimed to be caused from laser shows. Also, under new U.K. laws, if someone states they were injured by a laser, the burden of proof is on the laser show operator to prove they were using safe practices and light levels.

For this reason, you need to be proactive. Assume that someone in the audience might claim an injury. Keep video and other records to help prove that you operated safely and responsibly. This would have been very helpful in the 2009 Belgian incident, to quickly absolve the laser show operator (the injuries were caused by laser pointer misuse in the audience).

Know and follow safe practices

You should already know and follow the basic principles of laser show safety. Especially, NEVER scan audiences with pulsed lasers such as YAG or copper-vapor.

Measure and record your irradiance, before every show setup

A power meter should be a standard part of your show kit, just like a laser and a projector. ILDA believes it is essential to accurately measure the audience exposure at the point of closest access. Do this before every show setup, and record this data. You may wish to videotape this process, or be sure that an independent person such as the producer or venue manager witnesses the measurements being done.

Videotape every show (ideally, every projector)

ILDA also strongly recommends that you videotape EVERY audience scanning show. At the very least, have one camera or webcam continuously recording the laser part of the show. Even better, use one camera or webcam for each projector. Mount it on the front of the projector so it sees exactly what the laser sees. Keep the recordings for at least 1-2 months, since sometimes injury claims are made days or weeks after the event.

Operator supervision

ILDA believes that all audience scanning shows should be continuously supervised. The operator needs to see the scanned portion of the audience directly, or be in contact with audience observers.

This helps if the audience becomes unruly, such as floating reflective Mylar balloons into the beam path. This also helps if the operator sees laser pointers being misused by audience members. He or she can try to stop this, or can record the use via cellphone or camcorder, to help in case injuries are later claimed. (See above for a discussion about using video cameras throughout the show.)

Watch out for expensive cameras and video projectors

In addition to the audience's eyes, you should watch out for potential damage to cameras and video projectors. You need to be especially careful not to hit expensive, professional-level equipment often found in venues where laser shows occur. A single hit from a 50 mW beam can ruin the most costly part of the projector, the sensor/lens assembly.

Because it is nearly impossible to avoid cameras and camcorders brought in by the audience, ILDA considers that laser producers should not be responsible for damage to audience members' equipment -- especially if the show is at or below the MPE for eye exposure.