# NCEES Problem # 535

7 replies to this topic

### #1 Construction PE

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Posted 06 October 2011 - 12:19 PM

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
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!

#### Attached Thumbnails

Veteran

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Posted 06 October 2011 - 09:58 PM

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
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 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?

### #3 Construction PE

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Posted 07 October 2011 - 05:31 AM

QUOTE (IlPadrino @ Oct 6 2011, 10:58 PM) <{POST_SNAPBACK}>
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
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 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.

### #4 HP Junkie

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Posted 20 October 2011 - 02:45 PM

### #5 HP Junkie

HP Junkie

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Posted 22 October 2011 - 06:23 PM

### #6 Patrick1441

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Posted 07 April 2012 - 03:38 AM

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:

Source: http://law.justia.co...60824-1.31.html
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.

( 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.

### #7 Dano_PE

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Posted 07 April 2012 - 03:01 PM

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

### #8 Jayman_PE

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Posted 10 April 2012 - 09:11 PM

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