Question

post-test
all of the following are true about nitrogen plastic welders except:
a. they are more likely to burn the plastic than hot air plastic welders.
b. they produce less smoke than hot air plastic welders.
c. they may use an external nitrogen tank or nitrogen generator.
d. some units may be able to switch over to using air from the atmosphere.

Explanation:

To solve this, we analyze each option:

• Option B: Nitrogen plastic welders, by using inert nitrogen, reduce oxidation and thus produce less smoke than hot - air welders (which use air with oxygen that can cause more combustion - related smoke). This is true.
• Option C: Nitrogen plastic welders need a source of nitrogen, so they can use an external nitrogen tank or a nitrogen generator. This is true.
• Option D: Some nitrogen plastic welders are designed to be able to switch to using atmospheric air, which is a known feature. This is true.
• Option A: Nitrogen plastic welders, because nitrogen is inert and reduces oxidation, are less likely to burn the plastic compared to hot - air plastic welders (which have oxygen in the air that can promote burning). So this statement is false.

Answer:

A. They are more likely to burn the plastic than hot air plastic welders.