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What are the basic fundamentals of reading opacity in the field at my plant?

Before we start the smoke school certification test, we always have a mini-lecture (download mini-lecture) to explain the basic fundamentals of passing the certification test and how to read opacity in the field. The bible for EPA Method 9 visible emissions opacity evaluations is 40 CFR 60 Appendix A. In order to correctly evaluate opacity you must follow these guidelines, otherwise you will make significant errors in your evaluation. This is critical if you are a state or federal inspector. Your inspection may result in notices of violations for problems that do not exist. This error would cause all sorts of problems for the industrial plant you are inspecting. The company may challenge your inspections and report the error to your supervisor. The company may challenge your inspection in court. What size suit do you wear?  I hate being in court. These challenges would result in significant embarrassment to you and to your department. This court case resulted in an embarrassment to the inspector and his agency. 

Representatives from industrial plants or other non-regulating agencies should use the correct fundamentals when reading opacity. Your job is to document compliance with your permit and all regulations relating to air quality. Your mistakes could cost your company embarrassment when you receive notices of violations, fines, court appearances, and negative publicity.   This court case resulted in several plant staff being fired.

The opacity evaluator should follow basic fundamentals. Before we start the smoke school certification test, we always have a mini-lecture to teach the basic fundamentals of how to take the smoke school test and how to read opacity in the field. We start out with these fundamentals of how to read opacity in the field at your plant:

1.  How to choose an observation position- where to stand

1. Sun to your back

2. Winds blowing perpendicular to your line of view- from your left to your right- not coming at you or going away from you

3. Get back at least 3 stack heights to obtain a vertical angle of 18 degrees or less

4. How to make and use a Boudreaux Level to determine your vertical angle

5. Choose an observation position that allows a contrasting background. You can not read white smoke with white clouds in the background. You can not read black smoke with black clouds in the background.

6. How to use a Ringelmann smoke chart for black smoke

2. How to choose the correct observation point- where to look at and observe the plume

1. The densest part of the plume

2. No steam- at the tip of the smokestack before the plume spreads

3. Attached steam- touching the smokestack- observe at the end of the steam plume- the densest part of the plume after the steam ends or evaporates

4. Detached steam- not touching the smokestack- read before the steam starts or after the steam ends

3. The frequency of your observation readings

1. Take a reading every 15 seconds using a stopwatch

2. Read the opacity every 15 seconds for a minimum of 6 minutes to make a single set of readings

3. This makes 24 readings in 6 minutes

4. Sum up your readings

5. Determine the average opacity reading- Divide the total of the opacity readings by the number of readings

4. What do you do if your observation evaluation is out of compliance.

1. Notify your operator and plant manager immediately

2. Get permission to shut down the process and fix the problem

3. Conduct another evaluation after the problem is corrected

5.  How to record your opacity readings on the EPA Method 9 Form- Instructions for completing the Method 9 Form