Hazard warnings are signs and labels that form part of the third level of the Hierarchy of Controls, Information for Use. There are two standardized forms for machinery hazard warning labels in use globally: ANSI and ISO. Before thinking about labels, you need to complete a risk assessment.
Hazard warnings, including signs and labels, are a crucial part of the Hierarchy of Controls under the “Information for Use” category. There are two primary standardized systems for machinery hazard warning labels: ANSI and ISO. However, before considering labels, it’s essential to conduct a risk assessment.
ANSI Hazard Warning Labels
ANSI labels are widely used in the USA and frequently seen in Canada and Mexico. These labels must include a hazard alert symbol (a triangle with an exclamation mark) and a hazard keyword such as Danger, Warning, or Caution. They also feature a text panel with two or three parts:
- A description of the hazard,
- The potential consequences,
- The protective actions to prevent injury.
Pictograms may also be added for clarity, especially in multilingual workplaces where text alone may be insufficient. ANSI labels follow the ANSI Z535 series of standards.
ISO Labels
ISO labels address text translation and literacy issues by relying entirely on pictograms. Each shape and color combination has a standard meaning:
- A red circle with a diagonal slash: Prohibition
- A black triangle on yellow: Warning
- A white circle on blue: Mandatory
- A white square on green: Safety information
ISO labels are designed according to ISO 3864 and ISO 7010 standards.
Harmonized labels
In 2020, ANSI and ISO introduced a harmonized “wordless” label that combines ANSI’s layout and ISO’s standardized shapes and colours. Pictograms from both systems can be used.
We collaborate with Clarion Safety Systems to assist with label reviews and hazard warning label designs.
