Suddenly she realizes that the flame sensor cannot be totally blocked. The purpose of the flame on sensor is to shut off flame gases if the flame is extinguished. So she adjusts the business card to only partially block the flame on sensor. Now the flame lights properly and stays on. She removes the business card, replaces the flame shield, and begins to make analytical measurements. But she finds that the absorbance signals from her standard solutions are much noisier than she had previously encountered when the instrument was in a different location. She takes a close look at the flame (shown here). What's the problem and the solution?
 

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