Indoor pollution experts conducted an analysis of the paint used in ma

Question

Indoor pollution experts conducted an analysis of the paint used in many office buildings which revealed that the paint contains traces of lead. The lead seems to rise to the surface of the paint and escape into the building's air supply. Tests show that because of the chemical drying process, the lead is not discernible on the surface until the paint has been on the walls for at least six months. To meet safety standards, owners should repaint walls at least every six months, or cover the walls with a different material.

Which of the following, if true, would most weaken the conclusion above?

A) The indoor pollution experts had no clear understanding of why it took six months for the lead to become discernible on the paint's surface.
B) The indoor pollution experts neglected to examine the paint for traces of other toxic substances such as cadmium and mercury.
C) The amount of lead found on the surface of the paint after six months remained constant for the next two years. 
D) The indoor pollution experts found that even in those offices painted with a different brand of paint, traces of lead were still found in the air workers breathed.
E) The indoor pollution experts' research shows that the amounts of lead that come into contact with the air people breathe, even in the office buildings that used the greatest amount of paint, are too low to affect workers.

Archit3110 · Answer

option E The indoor pollution experts' research shows that the amounts of lead that come into contact with the air people breathe, even in the office buildings that used the greatest amount of paint, are too low to affect workers
provides alternate reasoning to make the conclusion of the argument break....

NeoNguyen1989 · Answer

E is the answer. here is the approach.

conclusion  : office buildings need to have walls repainted every six months or covered with different materials to meet the safety standard

premise  : lead is not discernible on the surface until six months later.

assumption   : after six months, the lead that is discernible on the surface will negatively impact on the safety of people breathing the air in the building

negative rephrasing  - negate the conclusion and have this 'office building managers  might not   need to have the walls repainted or covered with different materials because...'

review the answers:  
a. doesn't follow the negative rephrasing 
b. doesn't follow the negative rephrasing 
c. irrelevant
d. support the conclusion 
e. CORRECT - support the negative rephrasing

vishalsinghvs08 · Answer

I could be wrong here but Option E is still shaky and holds weaker grounds than option C

Conclusion - owners should repaint walls at least every six months, or cover the walls with a different material to meet safety standards

I could weaken it in multiple ways
 1. By saying they can do it in 2 years and not 6 month.

>> This is what option C is telling us. That it takes roughly 2 years for the paint to start dissipating into air. Repainting after atleast 2 years is fine, therefore.

2. By saying no matter when you do(6 months or 60 month), it may not impact the safety being discussed because there is no safety concern here

>>T his is what option E is telling us. However, i am still not sure of this because its not tied specifically to the conclusion. Amounts of lead that come in contact when? before 6 months(if yes, then please repaint sooner )? after n months(then atleast 6 months is fine)?
 
My analysis could be wrong and I am open to discuss and learn the correct approach. Thank you

DanTheGMATMan   KarishmaB  - Experts, please help.

DanTheGMATMan · Answer

You are right about the possible ways of weakening this conclusion. It could be that it doesn't need to be as frequent as the author claims, or that this concern isn't actually warranted to begin with. The author concludes that it needs to be done every 6 months, and E says this isn't necessary/won't make a difference.

The problem with C is that, once the paint has reached the surface at 6 months, it is potentially poisoning people the entire time it's there. I don't think they are saying that because the amount remains constant it isn't off-gassing and possibly harming people somewhat. You'd still want to go ahead and paint over it to meet safety standards.

KarishmaB · Answer

This is what the argument tells us:

The lead seems to rise to the surface of the paint and escape into the building's air supply. Tests show that because of the chemical drying process, the lead is not discernible on the surface until the paint has been on the walls for at least six months.

Options (C) vs (E)

We know that the lead rises to the surface and escapes into the building's air supply. It reaches a discernible level (there might still be some before that but the amount would be too small) on the surface in 6 months so it should be controlled at that time and not allowed to escape into the building's air supply. So it should be repainted before that.

C) The amount of lead found on the surface of the paint after six months remained constant for the next two years.

This does not mean that lead is not escaping from the surface. We are given that it escapes. If the amount is constant, it could be that it is constantly being replenished from the lower layers of the paint. With time, more and more lead is reaching the surface (from the lower layers) while it is escaping from the surface at the same rate. 
This option does not mean that we can paint after 2 years and that painting within 6 months is not essential. 
If an option had given us reason to believe it then you are right, it would have weakened our argument.

Option (E) says that whatever quantity of lead escapes. it is harmless. Then the owners do not need to repaint etc. Hence option (E) weakens our argument.

Answer (E)

SafSin28 · Answer

Is not E an assumption here? Because in the argument two problems occur: 1) The lead is visible on the surface and 2) The lead escapes into the air. The argument reaches the conclusion by solving the first problem. So it assumed the second effect is not a problem. E exactly does so. But D says the second effect is still a problem to reach a conclusion.

guddo · Answer

Indoor pollution experts conducted an analysis of the paint used in many office buildings which revealed that the paint contains traces of lead. The lead seems to rise to the surface of the paint and escape into the building's air supply. Tests show that because of the chemical drying process, the lead is not discernible on the surface until the paint has been on the walls for at least six months. To meet safety standards, owners should repaint walls at least every six months, or cover the walls with a different material. 
 
Which of the following, if true, would most weaken the conclusion above?

The argument assumes that  once the lead reaches the air, it creates a real safety problem, so repainting every six months or covering the walls is necessary . The best weakening answer is the one that shows the lead exposure is too small to matter.

(A) The indoor pollution experts had no clear understanding of why it took six months for the lead to become discernible on the paint's surface.

This does not weaken the conclusion much. Even if they do not know why it takes six months, the conclusion could still be correct if the lead level is dangerous.

(B) The indoor pollution experts neglected to examine the paint for traces of other toxic substances such as cadmium and mercury.

This does not weaken the conclusion. If anything, other toxins could make the situation seem worse.

(C) The amount of lead found on the surface of the paint after six months remained constant for the next two years.

This does not weaken the conclusion enough. A constant amount could still be unsafe.

(D) The indoor pollution experts found that even in those offices painted with a different brand of paint, traces of lead were still found in the air workers breathed.

This weakens the recommendation somewhat, because changing paint may not solve the problem. But it does not show that the lead level is actually harmless.

(E) The indoor pollution experts' research shows that the amounts of lead that come into contact with the air people breathe, even in the office buildings that used the greatest amount of paint, are too low to affect workers.

This is the best answer. If the lead reaching the air is too low to affect workers, then the recommended repainting or covering is unnecessary. That directly undercuts the conclusion.

Answer: (E)

Indoor pollution experts conducted an analysis of the paint used in ma

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Indoor pollution experts conducted an analysis of the paint used in ma

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