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Refrigeration & AC
EPA 608 Certification
Modern Technology & Industry Standards
Knowledge Check
Modern Technology & Industry Standards
Knowledge Check
Knowledge Check
1 / 15
What is the maximum allowable CO concentration in flue gases for a residential gas appliance?
A
200 ppm air-free
B
1000 ppm air-free
C
50 ppm air-free
D
400 ppm air-free
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