Engineer Boards

# NCEES Problem # 535

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Problem states:

An employee is assigned for an entire 8-hour shift to remove rivets by burning off the heads and punching rivets out with power tools. The rivets are coated with lead paint. This work has been determined to generate an airborne concentration of lead of 1,500 micrograms per cubic meter. The MINIMUM level of respiratory protection to this exposure required by Federal OSHA 1926.62 Subpart D is:

a) half-mask air purifying respirator with appropriate filters

B) helmet supplied-air respirator operated in continuous-flow mode

c) full-facepiece self-contained breathing apparatus (SCBA) operated in positive-pressure mode

d) half-mask or full-facepiece supplied-air respirator operated in continuous-flow mode.

d)half-mask or full-facepiece supplied-air respirator operated in continuous-flow mode. 1,500 micrograms/ m^3 is more than 1,250 micrograms/m^3 and less than 2,500 micrograms /m^3.

When I went to OSHA section 1926.62(f)(3)(i) it referred me to 1919.134(d)(3)(i) Table 1. See attached. However this table doesn't show the 1,250 micrograms or the 2,500 micrograms the NCEES answer talks about.

Do I have the wrong table? Or do the table "assigned protection factors" need to be multiplied by something? What am I not reading correctly here?

Any help would be appreciated!

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I think you're doing this right... you need to know that OSHA's PEL for lead, according to 1910.1025©(1), is 50 ug/m3 averaged over an 8-hour period. The given airborne concentration is given as 1500 ug/m3, so you need an APF of at least 30 (1500/50). According to the table,

a) 10

B) 25

c) 10000

d) 50

So I like d. I think they're trying to say an APF of 25 (1250/50) is not enough and an APF of 50 (2500/50) is sufficient. In other words, they're looking at it this way: answer B) provides sufficient protection for airborne concentrations of 1250 (50*25) which is not enough. answer d) provides sufficient protection for airborne concentrations of 2500 (50*50) which is enough.

Make sense?

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I think you're doing this right... you need to know that OSHA's PEL for lead, according to 1910.1025©(1), is 50 ug/m3 averaged over an 8-hour period. The given airborne concentration is given as 1500 ug/m3, so you need an APF of at least 30 (1500/50). According to the table,

a) 10

B) 25

c) 10000

d) 50

So I like d. I think they're trying to say an APF of 25 (1250/50) is not enough and an APF of 50 (2500/50) is sufficient. In other words, they're looking at it this way: answer B) provides sufficient protection for airborne concentrations of 1250 (50*25) which is not enough. answer d) provides sufficient protection for airborne concentrations of 2500 (50*50) which is enough.

Make sense?

Yes!! It does make sense now. Thank you so much!!! Great response.

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This problem came up for me as well. The 29 CFR 1926 has been updated to remove the table referenced in the solution of the problem! It looks like you used the same Mancomm book I'm studying with, which reflects the change detailed below:

Amendment(s) published August 24, 2006, in 71 FR 50191

Effective Date(s): November 22, 2006

22. In §1926.62, remove Table 1 in paragraph (f)(3)(ii) and revise paragraph (f)(3)(i) to read as follows:

* * * * *

(f) * * *

(3) * * *

(i) Employers must:

(A) Select, and provide to employees, the appropriate respirators specified in paragraph (d)(3)(i)(A) of 29 CFR 1910.134.

(B) Provide employees with a full facepiece respirator instead of a half mask respirator for protection against lead aerosols that may cause eye or skin irritation at the use concentrations.

© Provide HEPA filters for powered and non-powered air-purifying respirators.

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ONLY reference OSHA 1926.62 subpart D as it states in the question.

There is a table there. You will be in the "Not in excess of 2500ug/m3" zone.

The items on the right side are in order of minimum protection to max.

So look at the solutions stated in the problem. D is correct but solution C will still statify the requirement it is just over kill.

If they ask you to use a certian OSHA section use it. I made this mistake at first.

I have got in the habit of reading the problem 2-3 times. Hope that helps

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I have got in the habit of reading the problem 2-3 times. Hope that helps

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I know this is really old now but I'm looking at the latest OSHA 29 CFR 1926.62 Part D and there isn't any table. Is this just a really old problem?

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Sj - there should be a Table, it just may not be in the Section referenced - on other words the Section referenced may reference the Table location.

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