WSU alerts issued a warning Tuesday night asking students to avoid the outdoors due to unhealthy smoke from wildfires.

The warning notes that classes will still be in session and students should drive or use public transportation to get to class. Students should also limit their outdoor time to only walking between classes.

According to the Washington State Smoke Blog, most of the smoke in Eastern Washington is from fires in Montana. The blog warns those within the hazardous air area to set their air conditioners to re-circulation and stay indoors for the next couple of days at least.

According to the Centers for Disease Control and Prevention (CDC), wildfire smoke can cause difficulties breathing, chest pains, headaches, increased heartbeat, tiredness and asthma attacks. For those who already have health issues or are vulnerable, smoke can be more dangerous.

Dust masks, typically found in hardware stores, are meant for trapping large particles such as saw dust and the CDC recommends not using them. Instead, the agency recommends using a medical respirator or N95 mask, which can offer some protection from smoke.

Reporting by Rebecca White