When does it matter?

[jacknife76]

I am having an opinion difference with some on PPE requirements and when they apply.

EX: An MCC bus (line side of bucket breakers) has an AF category of 2. The load side of the bucket breaker is category 0. The bucket breaker is open (breaker off) and the electrician is doing work inside the bucket. The load side of the bucket breaker is de-energized and there is no exposed bus (which is categeory 2). However, the line side lugs of the breaker are live.

Does the electrician have to wear category 2 PPE?
I know very well that an arc flash can occur, even if the worker does nothing to cause it. How far do we go in requiring our people to wear proper PPE if there is no exposed bus and the "could happen" may be a long shot?

Is there documentation I can use to back this up?

I always err on the conservative side for these issues. But sometimes, too much protection can be harmful as well. Do I go too far in requiring category 2 PPE when the only exposed live parts are the line side breaker lugs?

I would love some thoughts on this one.

 

[iwire]

If the person is not wearing category 2 PPE and an accident does happen ..... (lets assume the person is OK) ...... how do you think OSHA will view it?

I think you would be getting some serious fines, just my opinion. :smile:

 

[jacknife76]

I agree!

I guess I am looking for a "you're not crazy!"

 

[billsnuff]

2004 70e

2004 70e

take a look at table 130.2c approach boundaries.

limited approach fixed part = 3'6"

restricted approach = 1'

prohibited approach = 1"

@ 301 to 750 volts

a qualified person inside the boundary needs appropriate PPE based on the AF study or 130.7c9a

'09 is in effect, don't have one yet...........

 

[richxtlc]

HRC2 vs HRC0

HRC2 vs HRC0

The primary concern is the HRC rating of the bus, as it presents the greatest hazard. The HRC of the load side of the breaker is only of concern when working on the load side. To eliminate the need for ppe while working on the bucket, remove the bucket from the MCC. You will still need the appropriate ppe when removing the bucket from the MCC.
In reference to the 70E tables, unless the fault current falls with the narrow definition that is stated in the notes, the tables are useless. A hazard analysis needs to be performed.