Yes, a thermal image camera is a good way, but a better way to instantly see the leak and the cfm amount of the leak-- try using the Alnor thermoanemometer Model 8565. Cheap on ebay for $100.
Plus the Alnor has a 4 foot reach. No need for silly smokers.
Along side of a fireplace with an 11 foot ceiling which has a .25 inch opening along the outer edge. Glen it is simple math. 9 cfm total at 450 fpm.
I would not allow the figure in a report if you worked for me.Nor would I let you covey that information to a client. I think the tool is useful just not in the manner you use it
I would never work for anyone but my valued customers. My customers love me and all my business comes from word of mouth. By the way, you can use your smoker if you want. Not me.
It seems like not only the features and the uses of the device seem to be overstated, but also the price is under-estimated. It seems to be closer to $300 on eBay.
Check ebay now, there is one for $ 100.00. Thermoanemanometer measures velocity in fpm, and with a simple calculation you can convert to cfm.