ABSTRACT
Residual hazards (those that cannot be designed out or guarded) require warnings-on the product, in the manual, or both. The legal requirement for an adequate warning is that it provide information about hazards connected to the use of products and how to avoid those hazards. In that regard, specific warnings are more effective than vague ones and warnings aimed at protecting users are more effective than those intended to avoid liability. Some product warnings are mandated by law or regulation, such as those required by the Federal Hazardous Substances Act. For products without specific warnings mandates, manufacturers often follow national or international voluntary consensus standards such as ANSI Z535.4 and ISO 3864-2 for on-product labels and ANSI Z535.6 for warnings in manuals. Testing warnings is desirable to ensure that they convey the intended information, using a testing protocol that is both valid and reliable.
