What are some different methods or tricks to breaking open seal offs to get the wires out. I can replace the seal offs if need be, but I need to save the wiring. I have hammered and chisseled the chico out before. What are other ways you guys have done. Thanks.
Breaking Seal Offs
- Thread starter DAWGS
- Start date
- Status
white vinegar....................... I've seen it work.
http://forums.mikeholt.com/showthread.php?t=106424&highlight=vinegar&page=3
(be sure to read Post 27)
http://forums.mikeholt.com/showthread.php?t=106424&highlight=vinegar&page=3
(be sure to read Post 27)
Cow
Senior Member
- Location
- Eastern Oregon
- Occupation
- Electrician
When I have stuck fittings that I can't get loose(seal offs, LB's, T's, etc)but still need to save the pipe, I'll rip down one side of it lengthwise with my cordless metal circular saw. I'll shove my big flathead into the crack to spread it, then it'll simply unscrew off the end of the pipe like it should of in the first place. I'll bet you could rip down both sides of a sealoff if you had to and split it apart like an oyster, then you'd have 360 degree access to the chico.
Cold Fusion
Senior Member
- Location
- way north
Iron ones will break using two hammers. Aluminum won't.
I've used a little disk grinder (~4") to cut a groove down the sides but not clear through. Then break with a couple of hammers. That work for both iron and aluminum.
Then you find out the dork didn't pack it very well and there is chico solid to the next sweep. That should be and executable offense.
cf
I've used a little disk grinder (~4") to cut a groove down the sides but not clear through. Then break with a couple of hammers. That work for both iron and aluminum.
Then you find out the dork didn't pack it very well and there is chico solid to the next sweep. That should be and executable offense.
cf
Power Tech
Senior Member
- Location
- Lebec, California
Power Tech
Senior Member
- Location
- Lebec, California
This is why I like this forum. I never herd that, I usually chip until I see copper and repull.
Rewire
Senior Member
- Location
- Lake of the Ozarks
a lttle LOX and aluminum will shatter
- Location
- Illinois
- Occupation
- retired electrician
It is not really an issue. Yes there is a reason for the seals, but if the atmosphere is really within the flammable range, you are probably dead unless you are on supplied air. The IDLH (Immediately Dangerous to Life and Health) level for many flammable vapors is about 10% of LEL (Lower Explosive Limit).WHAT TYPE OF ATMOSPHERE IS THE SEAL OFF IN?
metal blades and grinders?
there must be a reason for the seal off., but then again i may be over thinking things again!!
That being said, many plants that have classified areas have provisions to do "hot" work within those areas. Sometimes under shut down conditions, but other times using monitoring equipment to prove that the vapor level is well below LEL.
you must of spent some time in the "oil patch" i understand all of those items up to and including hot permits and sniffers, that does not neccesary mean that pulling out a grinder or saw in a classified are is s.o.p., how do we know the seal off is not located at a f.s. box containing an set of contacts that are not immersed?
thank you for the lesson though, there are alot of us junior members that are a little rusty, have not been in the patch for 20+ yrs.
- Location
- Illinois
- Occupation
- retired electrician
I didn't mean to suggest that you just use a spark producing tool any time you want to. You use the procedures that are in place to permit the use of such tools, and of course all of the circuits within the conduit have to be locked out before you attempt to break the seal.you must of spent some time in the "oil patch" i understand all of those items up to and including hot permits and sniffers, that does not neccesary mean that pulling out a grinder or saw in a classified are is s.o.p., how do we know the seal off is not located at a f.s. box containing an set of contacts that are not immersed?
thank you for the lesson though, there are alot of us junior members that are a little rusty, have not been in the patch for 20+ yrs.
As far as the information, most came from being a certified HazMat Tech B and working in a plant that is mostly Class I, Division 2.
impressive!, no dis respect implied in my previous post!, or was I questioning your experience. thanks.
when we worked bid jobs we used to put as much rmc toether as we could before putting it on the wall ceiling ect, as we were always limited to the amount of unions the boss would give us... they are not cheap!, but as you point out may be cheaper than the alternative. not everyone looks down the road, you learn that one the hard way.
new work I fully understand.....but retro work?....install a unf.. your most likely on T/M anyway on a job like this....or at least I would be. A tradesman should always look out for the next guy (electrician) down the road......But I know alot of folks will say, screw the next guy....
I guess I have this mindset, working 30+ years in electrical maint, and I would always say, "why didnt he do this, or that?" My pet peve, is backtaping split bolts or motor connections.....ALWAYS
I guess I have this mindset, working 30+ years in electrical maint, and I would always say, "why didnt he do this, or that?" My pet peve, is backtaping split bolts or motor connections.....ALWAYS
- Location
- Mission Viejo, CA
- Occupation
- Professional Electrical Engineer
Don,
You have mentioned IDLH several times before and you are definitely the expert in the subject here.
I?ve been thinking about methane. I know in sufficient quantities it is an asphyxiant but it isn?t toxic in the common sense of the term even in quantities significantly above LEL. I reviewed several MSDS documents. I also reviewed the following NIOSH pages:
NTIS Publication No. PB-94-195047: Documentation for Immediately Dangerous to Life or Health Concentrations (IDLH): Introduction
NIOSH Chemical Listing and Documentation of Revised IDLH Values (as of 3/1/95)
I may be reading them incorrectly, but it appears to me that a fair number of the chemicals (~30) are actually determined to be IDHL based on their LEL rather than any inherent toxicity. In other words, a Class I, Division 1 location would not necessarily be toxic although it would be considered IDHL.
Since gasoline is actually a blend of several hydrocarbons I checked the NIOSH Chemical Listing and Documentation of Revised IDLH Values and found most of the component hydrocarbons designated IDLH based primarily for their LEL rather than toxicity. The major exceptions were benzene and toluene although they tend to be a relatively small percentage of the process stream and ultimate product. I was surprised hydrogen wasn?t listed at all for LEL. It is often a major part of the process stream both for reforming and stripping.
The really nasty by-product is hydrogen sulfide which is almost as toxic as hydrogen cyanide. Depending on the feedstock, it can be produced in substantial quantities although if you can smell it; it hasn?t reached genuinely toxic levels.
My real question is what documentation or training has led you to the conclusion that Class I, Division 1 is automatically toxic where it could be IDHL for other reasons? As we discussed in some other thread, as a minimum, it may well be worth an FPN.
You have mentioned IDLH several times before and you are definitely the expert in the subject here.
I?ve been thinking about methane. I know in sufficient quantities it is an asphyxiant but it isn?t toxic in the common sense of the term even in quantities significantly above LEL. I reviewed several MSDS documents. I also reviewed the following NIOSH pages:
NTIS Publication No. PB-94-195047: Documentation for Immediately Dangerous to Life or Health Concentrations (IDLH): Introduction
NIOSH Chemical Listing and Documentation of Revised IDLH Values (as of 3/1/95)
I may be reading them incorrectly, but it appears to me that a fair number of the chemicals (~30) are actually determined to be IDHL based on their LEL rather than any inherent toxicity. In other words, a Class I, Division 1 location would not necessarily be toxic although it would be considered IDHL.
Since gasoline is actually a blend of several hydrocarbons I checked the NIOSH Chemical Listing and Documentation of Revised IDLH Values and found most of the component hydrocarbons designated IDLH based primarily for their LEL rather than toxicity. The major exceptions were benzene and toluene although they tend to be a relatively small percentage of the process stream and ultimate product. I was surprised hydrogen wasn?t listed at all for LEL. It is often a major part of the process stream both for reforming and stripping.
The really nasty by-product is hydrogen sulfide which is almost as toxic as hydrogen cyanide. Depending on the feedstock, it can be produced in substantial quantities although if you can smell it; it hasn?t reached genuinely toxic levels.
My real question is what documentation or training has led you to the conclusion that Class I, Division 1 is automatically toxic where it could be IDHL for other reasons? As we discussed in some other thread, as a minimum, it may well be worth an FPN.
- Location
- Illinois
- Occupation
- retired electrician
Bob,
I will have to dig my books out as I am retired from firefighting, but all of my hazmat classes they teach that for most flammable products the IDLH is about 10% of LEL.
Here is a MSDS for gasoline. It does not have an IDLH level, but the STEL (short term exposure limit) is 500 ppm and the LEL is 14,000 ppm. In this case OSHA would require respiratory PPE at 500 ppm if you are going to be exposed for over 15 minutes. The STEL would be a concentration that would be significantly lower than the IDLH concentration.
One of the chemicals used at a plant I often work at is acrylonitrile, with an IDLH of 85 ppm and LEL of 31,000 ppm. Another used at that plant is styrene with an IDLH of 700 ppm and LEL of 11,000.
I do see that there are a lot of the ones on the NIOSH list that the IDLH and the LEL are the same. It appears that when they changed the IDLH levels that they have made them equal to the LEL for the cases where they were previously above LEL. It looks like that what we were taught in the hazmat classes was not entirely correct.
As far as your last question, I can only say this.
If you really have a Class I, Division 1 location, I can not see permitting any one to enter the area without PPE suitable for the product as the IDLH for the products is equal to, or in a number of cases substantially less than the, LEL. I know that protection of people and selection of PPE for people is not the purpose of the area classifications, but based on the criteria used to classify the areas, the very fact that an area has been classified as a division 1 area should indicate that extreme caution is required to even enter the area.
I will have to dig my books out as I am retired from firefighting, but all of my hazmat classes they teach that for most flammable products the IDLH is about 10% of LEL.
Here is a MSDS for gasoline. It does not have an IDLH level, but the STEL (short term exposure limit) is 500 ppm and the LEL is 14,000 ppm. In this case OSHA would require respiratory PPE at 500 ppm if you are going to be exposed for over 15 minutes. The STEL would be a concentration that would be significantly lower than the IDLH concentration.
One of the chemicals used at a plant I often work at is acrylonitrile, with an IDLH of 85 ppm and LEL of 31,000 ppm. Another used at that plant is styrene with an IDLH of 700 ppm and LEL of 11,000.
I do see that there are a lot of the ones on the NIOSH list that the IDLH and the LEL are the same. It appears that when they changed the IDLH levels that they have made them equal to the LEL for the cases where they were previously above LEL. It looks like that what we were taught in the hazmat classes was not entirely correct.
As far as your last question, I can only say this.
If you really have a Class I, Division 1 location, I can not see permitting any one to enter the area without PPE suitable for the product as the IDLH for the products is equal to, or in a number of cases substantially less than the, LEL. I know that protection of people and selection of PPE for people is not the purpose of the area classifications, but based on the criteria used to classify the areas, the very fact that an area has been classified as a division 1 area should indicate that extreme caution is required to even enter the area.
- Location
- Illinois
- Occupation
- retired electrician
Bob,
I just took another look at the NIOSH table. The IDLH values that have LEL next to them are set at 10% of the actual LEL. I expect that is what I was being taught in the hazmat classes.
From the NIOSH Pocket Guide to Chemical Hazards.
I just took another look at the NIOSH table. The IDLH values that have LEL next to them are set at 10% of the actual LEL. I expect that is what I was being taught in the hazmat classes.
From the NIOSH Pocket Guide to Chemical Hazards.
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