Most employees in Washington State are entitled to accrue and use sick leave to care for your own health or the health of a family member. An employer cannot fire you for using your sick leave appropriately.
If you are outside of Seattle or Seatac, you should be accruing 1 hour of sick leave for every 40 hours you work regardless of the size of your employer. If you are a salaried employee (overtime exempt) and you work outside of Seattle, you are not entitled to accrue sick leave. See Paid Sick Leave.
If you are in Seattle, you should be receiving 1 hour of sick leave for every 40 hours you work. If you work for a large employer, you should accrue 1 hour for every 30 hours you work. If you are a salaried employee (overtime exempt), you are still entitled to accrue sick leave in Seattle. See Paid Sick & Safe Time Ordinance – Fact Sheets (PDF)