I work at a chemical processing plant. When I arrive at work, I spend about ten minutes putting on protective safety gear, including specially treated work pants and jacket, hood, safety glasses, gloves, and boots. At the end of the day, I spend another ten minutes or so taking all of this gear off and stowing it properly to be cleaned. We aren't paid for the time we spend suiting up and stripping down. Should we be?
It depends on whether you are represented by a union and, if so, what your collective bargaining agreement says. The Supreme Court has said that time spent "changing clothes" is a proper subject of collective bargaining. This means the union and the employer may negotiate how much, if any, of this time will count as work time, for which employees must be paid.
Although you might think that your safety gear isn't really clothing, the Supreme Court sees it differently when it comes to collective bargaining agreements. The Court decided a case in which workers wore protective items similar to yours, and found that most of it counted as "clothes" within the meaning of the law. Therefore, the Court found, the union could bargain away employees' rights to be paid for the time they spent putting in on and taking it off.
If your workplace isn't unionized, the rules are different. For non-union employees, time spent putting on safety gear is treated differently from time spent changing clothes for convenience. The Supreme Court has found that time spent putting on protective gear that is required to do the job is compensable time; that is, it counts as hours worked, for which you must be paid. Your job exposes you to hazardous chemicals. You would be unable to work safely without protective gear. This means you are entitled to be paid for the time you spend putting it on and taking it off.
On the other hand, if your job required you only to get dirty (and not to handle dangerous materials), you wouldn't be entitled to pay for the time it takes you to change clothes. If, for example, you worked as a landscape gardener, you might expect to get quite dirty. Your employer might offer a place for employees to change in and out of their work clothes and to shower. But this would be purely for the convenience of employees. It is not necessary to do the job. You could commute in your work clothes, and drive home sweaty and covered in dirt, if you wished. Because changing and bathing would not be required to do this job, any time you chose to spend on these activities would not be compensable.