Even smoke trapped in a smoker's clothing may trigger an attack. Stay away from them until they dry or wear a respirator mask. Ask coworkers to give them up. Some gyms specifically ask users to leave perfumed sprays and deodorants at home. Don't use your home fireplace or wood-burning stove.
Some gas stoves leak cooking gas, which can be a trigger.
Get your stove checked. Buy non-scented varieties. A written treatment plan from your doctor takes the guesswork out of managing asthma. In short, it's the greatest thing since metered dose inhalers. If you don't have one already, click below to print out your plan, then take it to your next doctor's visit.