Emergency exit is often translated as '紧急出口' in Chinese. It is pronounced as 'jǐn jí chū kǒu'
紧急 (jǐn jí) means emergency
出口 (chū kǒu) means exit

If you want to ask where the emergency exit is, you can say 紧急出口在哪儿 (jǐn jí chū kǒu zài nǎ ér ) ? or 紧急出口在哪里 (jǐn jí chū kǒu zài nǎ lǐ )?
在哪儿 (zài nǎ ér ) or 在哪里 (zài nǎ lǐ ) means where is xxx?