Danger - Do Not Switch On - Safety Signs by Caledonia Signs

Used to warn that operating a particular electrical switch, circuit, or piece of equipment could cause harm to people, damage to equipment, or disrupt important work in progress. This warning is most often applied when machinery is undergoing maintenance, repair, or installation, and energizing it could pose a direct safety risk to workers or compromise the integrity of the task being carried out. The sign communicates an immediate prohibition that must be strictly followed until it is safe to restore power or operation.

These signs are typically placed directly on or very close to the relevant control point—such as a switch, circuit breaker, or machine control panel—so the warning is seen before anyone can operate it. Common settings include factories, workshops, construction sites, laboratories, and areas where electrical or mechanical systems are in service. They are especially important in lockout/tagout procedures, where they serve as part of a broader safety system ensuring that equipment remains de-energized while work is underway.

The main reason for using a “Do Not Switch On” sign is to prevent accidents such as electric shocks, moving-part injuries, or fires that could occur if equipment is powered unexpectedly. It also helps avoid costly damage to systems that are mid-maintenance or testing. In many workplaces, safety regulations require that all equipment under maintenance must be clearly marked to prevent accidental operation, making this sign not only a precaution but a compliance measure.

For maximum effectiveness, the sign should be placed in a position where it is impossible to overlook, ideally physically attached to the control device it refers to. It should remain in place until all work is complete, tested, and confirmed safe for operation. When used correctly, this type of warning is a simple yet essential safeguard against preventable injuries and operational hazards.

Materials Explained

Below is a more detailed description of the materials this particular safety sign is available in. Helping you decide which sign option is most suitable for your application.

Rigid Plastic: This lightweight, gloss white PVC is resistant to weather, moisture, chemicals, and general wear and tear, making it suitable for harsh environments. Its smooth, solid surface allows for crisp printing of text and graphics, enhancing readability and visual impact. Businesses who choose Rigid Plastic signs benefit from fewer replacements and minimal maintenance, making it a practical investment for reliable and effective safety signs.

Self-Adhesive Vinyl: Self-adhesive vinyl is easy to apply and it’s budget-friendly. Its adhesive backing allows for easy application to a variety of surfaces such as glass, metal, plastic, and painted walls, which simplifies installation and reduces setup time. Self-adhesive vinyl provides a clean, professional finish that suits many indoor environments including offices, retail, industrial sites, and vehicles. It is more affordable than many other material types and allows for custom shapes, colours, and graphics.