What is backdrilling of a vent hole and why is it done?
What will be an ideal response?
Backdrilling is cutting a larger hole behind the portion of the vent hole that touches the plastic sheet. This larger hole gives greater air flow and allows faster application of the vacuum.
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Which of the following serves as the introduction to the NEC® and provides an overview of the book?
a. NEC Article 90 b. NEC Article 100 c. NEC Section 240.2 d. NEC Section 250.52
What is carbon dioxide (CO2) a by-product of?
What will be an ideal response?
Explain what technical standards are and how they are used in the E&C industry
What will be an ideal response?
How many Btus of heat are removed per hour when the water at a flow rate of 10 lbs. per minute is cooled 15°F? (Water weighs 8.33 lb. per gallon.)
What will be an ideal response?