Mark Twain once famously quipped, “Work is a necessary evil to be avoided.” Though many employers might question Twain’s work ethic, there are certainly times when going to work can be harder than its worth. In these moments, you may have a good reason for requesting time off from work. The different reasons for calling off work can be grouped into four categories: illness, family, emergency, and personal time.

Too Sick to Work

For most workers, unexpected days or time off is often called “sick days.” This is because one of the most common and best reasons to request time off from work is because you’re too sick to be effective. Illness can not only affect your productivity and well-being, but also it can actually spread to other workers if you are sick with a contagious sickness such as the flu. Bosses are sympathetic about sick workers, particularly when those workers could potentially make other workers sick and cut down on productivity even further.

Family Problems

Oftentimes, we work to help support our families. By this very logic, then, staying home to support a family member is a perfectly good reason to request time off from work. Whether you need to stay at home to care for a sick spouse or kid, or if you have to attend the funeral for a parent or aunt, your boss will understand why it is more important for you to be with your family than it is for you to be at work. Just as your productivity and focus can suffer when you’re sick, so too will you likely be unable to work as well as you could normally if you are worried about your family.

Unexpected Emergencies

Unexpected things happen. These can range from a burst pipe to a colossal snowstorm. In either event, taking a day or two off to deal with unexpected emergencies is another good reason to request time off from work. When your attention is split between your work and some unforeseen accident or emergency, you’re essentially giving your job half of your attention and effort. In these situations, it’s best to take time to deal with the emergency and then return to work.

Personal Time

Look, your life can be hectic sometimes, what with being sick, and your aunt’s funeral and this massive snowstorm. Sometimes, in order to be the best employee you can be, you need to take a breather and relax. Taking a day to rest and relax and regroup is the final good reason for requesting time off from work. By taking care to improve your personal well-being, you put yourself in a better position to improve your professional performance.