The company came while my husband was home with our son(4 yrs old at the time)and dog. Iwas out for the day. While the truck was hooked up and backed up into our garage he began to clean the ducts. Just as he was about to finish our carbon monoxide detectors started alarming. The technition finished the job,and told my husband this was no big deal and to just open the windows in our house. My husband did this,but the alarm would not stop. He than began to feel ill(headache adn nausea). He decided to go to our nearest fire station to see if there was something else he could do to get the alarm to stop. The fire department then despatched a truck to our address to make sure it was safe for the family to be in the house. As it turned out the carbon monoxide levels were 3 times the safe amount,which was measured with some gadget the fire department had,and we were not allowed back in the house for over 2 and a half hours. The fire dept. called enbridge to make sure that it was not a gas leak from the furnace, as it turned out it was faulty equipment from the duct cleaning company. We had to remain outside our house with the fire crew with all the doors and windows open,the furnace running,until it was safe to return inside. Needless to say we are now affraid to have any company clean our ducts.