Arc Flash Forum
https://brainfiller.com/arcflashforum/

Hard Hats
https://brainfiller.com/arcflashforum/viewtopic.php?f=5&t=1086		 Page 1 of 1
Author:  dmaynor [ Wed Apr 28, 2010 10:32 am ]
Post subject:  Hard Hats
My question is does anyone have any information on the FR testing of hard hats? The typical rating is E and G and that seems to be about conductivity. I want to know if it's going to melt!
Author:  Zog [ Wed Apr 28, 2010 1:02 pm ]
Post subject: 
dmaynor wrote:
My question is does anyone have any information on the FR testing of hard hats? The typical rating is E and G and that seems to be about conductivity. I want to know if it's going to melt!


Hugh? Ring ring....
Author:  elihuiv [ Wed Apr 28, 2010 1:14 pm ]
Post subject: 
Hardhats and melting/igniting

Good question. Most have never been tested. I chair a taskforce on ASTM F18 to develop a test method to be added to specifications going forward.

First the good news. Rarely have hardhats hurt workers. I know of NONE from arc flash except when something underneath the hardhat ignited i.e. a melting hairnet (could have happened but not to my knowledge).

Polyethylene and Polycarbonate from one manufacturer have been tested and found tough to iginite. Igniting a non arc-rated headcovering, etc under the hardhat is your worst enemy. They work pretty darn good. I have tested some side impact hard hats with not so good results. Use the normal ones unless you have less than 8 cal exposure. If you are following NFPA 70E or CSA Z462 your hardhat will be covered at a pretty low level. I recommend covering hardhats at about 20 cal or less even if using a shield and balaclava. Most interpret 70E requiring this at 8 cal but that is really in the tables and not applicable to calculated situations. That works for me though since the data would support covering at some point.
Author:  Zog [ Wed Apr 28, 2010 1:24 pm ]
Post subject: 
Thanks Hugh. Here are some aftermath photos of arc flash accidents, hard hats stayed intact.

Attachments:
250456A.pdf [169.24 KiB]
Downloaded 309 times
Author:  dmaynor [ Wed Apr 28, 2010 4:41 pm ]
Post subject: 
Do you know if those hard hats were regular hard hats or if they were the high heat type? I only just found out they have some made from the same material as fire fighter hard hats are made of. According to Hugh regular hard hats work just fine also. I just don't want to make the wrong decision here. Hugh also talked about not using a hard hat if going over 20 cal but I think the best I have seen for face shields is 12 cal. Is there a better one?
Author:  anthonyfuller [ Mon May 03, 2010 5:48 am ]
Post subject: 
Safety of Stickers?

Many facilities require stickers to be placed on that you went through their safety program. Now, I've seen some arguments on if the sticker's adhesive will possibly react in a way that would deteriorate the hard hat. However, would said stickers/adhesives in an arc flash act as a fuel? I believe the answer is no, minimal or needs more testing.

I see one sticker from the picture posted on the back of the hard hat, but it wasn't exposed to the arc from what I can tell.

Thoughts?
Author:  Zog [ Mon May 03, 2010 5:56 am ]
Post subject: 
anthonyfuller wrote:
Many facilities require stickers to be placed on that you went through their safety program. Now, I've seen some arguments on if the sticker's adhesive will possibly react in a way that would deteriorate the hard hat. However, would said stickers/adhesives in an arc flash act as a fuel? I believe the answer is no, minimal or needs more testing.

I see one sticker from the picture posted on the back of the hard hat, but it wasn't exposed to the arc from what I can tell.

Thoughts?


There is some verbage in OSHA about sticker on class E hard hats, basially they are allowed but should be minimized and can pnly be placed in certian areas of the hat. Now you are in MI so you need to follow MIOSHA, which has some stronger verbage against using stickers on hard hats.
Author:  Vincent B. [ Mon May 03, 2010 6:40 am ]
Post subject: 
anthonyfuller wrote:
Now, I've seen some arguments on if the sticker's adhesive will possibly react in a way that would deteriorate the hard hat.


It's not only that it could react, it's also that you can't visually inspect the hard hat underneath the sticker.
Author:  Zog [ Mon May 03, 2010 8:28 am ]
Post subject: 
Vincent B. wrote:
It's not only that it could react, it's also that you can't visually inspect the hard hat underneath the sticker.


Right, and some labels can be conductive, which is why there is a requirement to not have them close to the rim of the hard hat, I think it is 3/4" but I do not have ANSI Z89.1 handy.

OSHA dances around the requirements here, basically saying if you alter the hard hat (e.g add stickers) you have to either have it apporved from the manufaturer or prove the safety of the hard hat is nto dimished (Yeah right)

http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=27272
Author:  ChevsMark [ Tue Aug 10, 2010 11:10 am ]
Post subject: 
[font="Comic Sans MS"][SIZE="3"]My hard hat has its rating molded on the inside at the back, it says:
Complies with ANSI Z 89.1 CLASS G E C TYPE 1
If you look, every hard has has its rating molded in as part of the mold process.[/size][/font]
Author:  elihuiv [ Mon Aug 16, 2010 7:49 am ]
Post subject: 
Hardhats and melting/igniting

The ANSI standard has VOLTAGE requirements tested at VERY LOW amperage to see if the hard hat will allow shock. There is no arc rating currently on hard hats. We are working on a test method right now and in will be voted on in the ASTM F18 committee as a subcommittee ballot.

I can't speak for all hard hats but my experience syncs with Zog. I have only seen a few melt to hurt anyone and they were strange situations. Very high energy. I recommend using NFPA 70E guidelines when possible and the hood is covered at about 25 cal/cm2.
Page 1 of 1 All times are UTC - 7 hours
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
http://www.phpbb.com/