Can a laser cutter run unattended during a long job?

Question

Accepted Answer

No.

No. Treat every laser job as one that an authorized person stays with for its whole duration, able to see the job and stop it. MIT says never leave an operating laser cutter unattended and observe the cutting or engraving process, and Temple University says to remain with the cutter during operation because of the fire and flare-up risk. Overnight runs, stepping out to teach elsewhere and walking away between periods are not options; this applies to enclosed Class 1 or Class 2 machines, and an open-frame or Class 4-in-normal-use machine is not covered and needs a laser safety officer and written program first. An authorized person stays with every laser job, before, during and after A left-to-right timeline of four boxes: start only a job you can watch to the end, job runs, job ends, and then stay with the machine with the lid closed and the exhaust running for the interval your manual or program specifies. A band beneath says an authorized person stays with it, able to see the job and stop it, for its whole duration. Below left, a list of things that are not options: overnight runs, stepping out to teach elsewhere, walking away between periods, and relying on a camera or alert instead of a person. Below right, cameras, remote alerts and suppression systems add protection but do not replace someone present. A strip at the bottom says any flame means stop and do not open the lid to look. Start only a job you can watch to the end Job runs Job ends Stay with it: lid closed, exhaust running, for the interval in your manual or program An authorized person stays: able to see the job and able to stop it Not options overnight runs stepping out to teach elsewhere walking away between periods a camera or alert with no one there Extra protection cameras, remote alerts, suppression systems: they add protection, but they do not replace someone present Any flame: stop. Do not open the lid to look. The watch does not end when the job does. Cameras and alerts help, but they never stand in for a person. This applies to enclosed Class 1 or Class 2 machines; open-frame machines are not covered. Cameras, remote alerts and suppression systems add protection, but they do not replace someone present. Only start a job you can watch to the end. The watch also does not end when the job does: stay with the machine, with the lid closed and the exhaust running, for the interval your manual or program specifies. MIT lists the usual contributors to cutter fires: not observing the machine, incorrect settings, insufficient exhaust, unsuitable material, dirty optics and a machine that is not cleaned out regularly. Every one of them is something an attentive operator can catch. If you see any flame, stop. Use the emergency stop or the switch you were trained to use, do not open the lid to look, move students away, and follow your school’s written fire and evacuation procedure. If the fire alarm sounds during a job, evacuate and never return; hit the emergency stop on the way out only if that takes no longer than leaving.

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