What types of testing can be used to identify substance impairment?

The answer is C, which identifies urine, saliva, breath, and hair follicle tests as methods for detecting substance impairment. This is correct because each of these testing methods has unique advantages for identifying various substances and can provide different types of information about an individual’s drug or alcohol use.

Urine tests are commonly used due to their cost-effectiveness and ability to detect a wide range of substances. Saliva tests offer a non-invasive method for collecting samples and can provide quick results, making them useful for on-the-spot testing. Breath tests are particularly effective for detecting alcohol impairment, as they measure the concentration of alcohol in a person's breath. Hair follicle tests, while usually more expensive and taking longer to yield results, can provide a longer detection window for substance use, identifying substances that may have been consumed over the past months.

Other methods are limited in scope or application. For instance, blood tests are not the only form of testing available and are more invasive and typically used in specific situations, like post-accident testing. Visual inspection alone does not provide objective evidence of impairment and relies heavily on subjective judgment, which can be unreliable. Thus, the combination of these various testing methods provides a more comprehensive approach to identifying substance impairment in the workplace.