diff --git a/components/app.js b/components/app.js
index f04451b..8edb4e5 100644
--- a/components/app.js
+++ b/components/app.js
@@ -261,6 +261,11 @@ export default class App extends Component {
 		this.connect(connectParams);
 	}
 
+	isChannel(name) {
+		// TODO: use the ISUPPORT token if available
+		return irc.STD_CHANNEL_TYPES.indexOf(name[0]) >= 0;
+	}
+
 	executeCommand(s) {
 		var parts = s.split(" ");
 		var cmd = parts[0].toLowerCase().slice(1);
@@ -281,9 +286,8 @@ export default class App extends Component {
 			this.client.send({ command: "JOIN", params: [channel] });
 			break;
 		case "part":
-			// TODO: check whether the buffer is a channel with the ISUPPORT token
 			// TODO: part reason
-			if (!this.state.activeBuffer || this.state.activeBuffer == SERVER_BUFFER) {
+			if (!this.state.activeBuffer || !this.isChannel(this.state.activeBuffer)) {
 				console.error("Not in a channel");
 				return;
 			}
diff --git a/lib/irc.js b/lib/irc.js
index 6766a1b..b48f8dc 100644
--- a/lib/irc.js
+++ b/lib/irc.js
@@ -13,6 +13,8 @@ export const ERR_SASLTOOLONG = "905";
 export const ERR_SASLABORTED = "906";
 export const ERR_SASLALREADY = "907";
 
+export const STD_CHANNEL_TYPES = "#&+!";
+
 var tagsEscape = {
 	";": "\\:",
 	" ": "\\s",