OSHA Warning This Machine Is Automatically Controlled And May Start At Any Time Sign Stickers

This sign warns workers that the machine's operation is controlled by an automatic system such as a PLC, SCADA system, or remote controller and can therefore start, stop, or change operation at any moment without a local operator present. This is a critical warning for workers who might assume a machine is safe to approach simply because no one appears to be operating it.

A machine under automatic control may start for reasons not obviously visible to a nearby worker such as a scheduled program cycle, a remote command, or a sensor trigger. This distinction matters for lockout/tagout compliance: OSHA 29 CFR 1910.147 specifically requires that automatically controlled machines be treated as potentially energized at all times and that lockout/tagout be performed before any servicing, regardless of whether a local operator is present.

Post on the machine control panel, on all access and maintenance doors, and at any worker approach position. This sign is especially important for machines in semi-attended or unattended areas where workers may approach without knowing whether the machine is in an active automatic control cycle.

OSHA 29 CFR 1910.147 (Control of Hazardous Energy / Lockout Tagout) specifically addresses the hazards of automatically and remotely controlled equipment. OSHA 29 CFR 1910.212 (General Machine Guarding) provides the broader machine hazard communication requirement that supports automatic control signage.

Warning is appropriate under ANSI Z535.4 for automatically controlled machines where unexpected activation presents a significant but not immediately life-threatening hazard. For high-risk automatically controlled equipment where unexpected activation could cause fatal injury, Danger is more appropriate. Your facility's hazard assessment should determine the correct signal word.