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OT: is heat gun stripping old paint really a lead hazard?

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  • OT: is heat gun stripping old paint really a lead hazard?

    I'm trying to figure out how to go at a ton of elaborate woodwork in a renovation project. I had bad experience 20 years ago with the original Peel-Away dripping all over the oak floors. I find heat stripping works pretty well with proper technique: a gun not a torch, and move it around a lot to heat evenly and lift off large segments. You still are left with nubs and streaks to clean up with stripper and a scotchbrite, but >95% of really thick paint is gone.

    The question is the hazard, especially if I want to hire college kids to help. Some info sources scream 'lead vapor!!' while others reasonably point out that lead oxide vaporises at higher temps than a 800F heat gun can possibly create.

    properties of lead oxide:
    Melting Point: 888 C (1663 F)
    Boiling Point: 1477°C (2691°F)
    Vapor Pressure: 10 @1085°C

    Any of you knowledgeable and scientific guys have input on this issue?
    Location: Jersey City NJ USA

  • #2
    There will always be some vapor escaping from a liquid even if it is nowhere near boiling point. Think about a glass of water sitting on the counter. Does it stay there indefinitely or does it eVAPORate? Room temperature is far less than half the boiling point. If you don't get anywhere near the melting point you shouldn't have to worry about that - BUT you will have to worry about particulates and dust escaping and floating around in the air. If you have lead paint, you shouldn't be removing it without a breathing filter of some sort. There's no escaping the fact that there will be airborne particulates which contain lead.

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    • #3
      Lead pigment might also be one of the lead carbonates (white lead)
      CNC machines only go through the motions.

      Ideas expressed may be mine, or from anyone else in the universe.
      Not responsible for clerical errors. Or those made by lay people either.
      Number formats and units may be chosen at random depending on what day it is.
      I reserve the right to use a number system with any integer base without prior notice.
      Generalizations are understood to be "often" true, but not true in every case.

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      • #4
        Have you tested the trim paint, all layers for lead?
        At the very least, lead approved respirators, disposable gloves. Don't heat the paint to the smouldering point, HEPA vac, don't sweep, use tack rags for molding, wall and floor wipe down.
        Last edited by reggie_obe; 12-20-2020, 04:10 PM.

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        • #5
          If you want to hire people (even starving student for cash) to help for sure consult the local regulations. Doing it your self - make your own choices, but take the usual precautions. If I'm using heat on old paint, real respirator cartridges and good ventilation. Sanding it? just good N95 or whatever. Check local regs for disposal - some allow you to just wrap it in newspaper and toss in the garbage; other not so.

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          • #6
            To answer your questions, does a fat dog fart?

            Comment


            • #7
              Some interesting information: https://www.tri-techtesting.com/Lead...nceptions.html
              IMHO, I would avoid advice on any website associated with Bob (Oh, that what a hammer looks like) Villa.

              Comment


              • #8
                The Peel-away folks used to claim that their highly alkaline stripper reduced the hazards of lead paint. I never looked farther into it, but they do not claim that anymore.

                Everyone knows that a lump of lead will jump off the table and poison you....
                CNC machines only go through the motions.

                Ideas expressed may be mine, or from anyone else in the universe.
                Not responsible for clerical errors. Or those made by lay people either.
                Number formats and units may be chosen at random depending on what day it is.
                I reserve the right to use a number system with any integer base without prior notice.
                Generalizations are understood to be "often" true, but not true in every case.

                Comment


                • #9
                  I think you would be scorching wood long before anything hazardous would be released.
                  I just need one more tool,just one!

                  Comment


                  • #10
                    Originally posted by challenger View Post
                    To answer your questions, does a fat dog fart?
                    It is impolite to answer a question with another question.

                    -D
                    DZER

                    Comment


                    • #11
                      Side story...
                      I grew up in an old farm house in NY.
                      My mother scraped all the layers of old paint off the clapboard siding of the whole house
                      using a propane torch and a putty knife. My father replaced all the rotten overhangs and
                      lookouts that carried the round rain gutters with Brazilian mahogany. Took them years to
                      restore this house, of some historical significance, built in 1902.
                      My parents sold the house when they retired to move to another house, and this place was
                      totally fixed up and perfect. Needed nothing.

                      The new owners cut off the mahogany overhangs, installed square gutters, and put up
                      vinyl siding ! ! ! ! ! ! ! ! Tore down the new wood shed and put in an in-ground pool ! ! !

                      All that work, years of work, for nothing.

                      -Doozer
                      DZER

                      Comment


                      • #12
                        The only things I remember from replacing several 100 year old steel railway bridges, with layers of lead paint was that the burners who cut them up had to have a blood test for lead before the job started, another one when it was finished, and were advised to drink plenty of milk. Why the milk, I don't know, but that was the advice at the time, 25 years ago.

                        If you are doing a restoration involving stripping layers of wall paper, and come across very old green paper, thats probably got arsenic in it-----.
                        'It may not always be the best policy to do what is best technically, but those responsible for policy can never form a right judgement without knowledge of what is right technically' - 'Dutch' Kindelberger

                        Comment


                        • #13
                          Originally posted by eKretz View Post
                          There will always be some vapor escaping from a liquid even if it is nowhere near boiling point. Think about a glass of water sitting on the counter. Does it stay there indefinitely or does it eVAPORate? Room temperature is far less than half the boiling point. If you don't get anywhere near the melting point you shouldn't have to worry about that - BUT you will have to worry about particulates and dust escaping and floating around in the air. If you have lead paint, you shouldn't be removing it without a breathing filter of some sort. There's no escaping the fact that there will be airborne particulates which contain lead.
                          Except that the melting point is 1663 F and it will not simply sublimate from a solid. Lead Carbonate was mentioned, I found The thermal decomposition of lead(II) carbonate to produce oxide lead(II) and carbon dioxide. This reaction takes place at a temperature of over 315°C. As for lead oxide: Lead (IV) oxide is thermally unstable and it tends to decompose into lead(II) oxide and oxygen upon heating. Whereas when lead(II) oxide is heated to around 450-480 °C, it forms lead(II,IV) oxide, also known as red lead or triplumbic tetroxide.

                          All of these temps are beyond the range of a 800 deg heat gun, especially one used properly. Also saw this on https://www.house-painting-info.com/...-paint-removal about using IR heating:
                          1. Metallic lead vaporizes at 1,000°F (the temperature at which heat guns operate.) Lead oxide used in paint most likely vaporizes at 800° F. The mid-range infrared heat waves heat the paint and wood in 20-60 seconds only to 400-600º F. Therefore, dangerous lead fumes are not released from the heated paint.

                          I'm trying not to let my natural skeptic get the better of me, like @jtiers saying "Everyone knows that a lump of lead will jump off the table and poison you...." Both my grandpas were metalworkers in the 1920s-50s when guys were swimming in everything from asbestos to benzene. Both lived to around 80, one died of emphysema from smoking 3 packs a day for decades, the other of heart disease.
                          Location: Jersey City NJ USA

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                          • #14
                            Originally posted by eKretz View Post
                            Think about a glass of water sitting on the counter. Does it stay there indefinitely or does it eVAPORate?

                            Think about a glass of water sitting on the counter. Does it stay there indefinitely or does it eVAPORate? Thats yer chit!!

                            Yeah numb sckulls. Dont melt lead or anything else unless you talk to your....

                            JR

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                            • #15
                              Originally posted by gellfex View Post

                              Except that the melting point is 1663 F and it will not simply sublimate from a solid. Lead Carbonate was mentioned, I found The thermal decomposition of lead(II) carbonate to produce oxide lead(II) and carbon dioxide. This reaction takes place at a temperature of over 315°C. As for lead oxide: Lead (IV) oxide is thermally unstable and it tends to decompose into lead(II) oxide and oxygen upon heating. Whereas when lead(II) oxide is heated to around 450-480 °C, it forms lead(II,IV) oxide, also known as red lead or triplumbic tetroxide.

                              All of these temps are beyond the range of a 800 deg heat gun, especially one used properly. Also saw this on https://www.house-painting-info.com/...-paint-removal about using IR heating:
                              1. Metallic lead vaporizes at 1,000°F (the temperature at which heat guns operate.) Lead oxide used in paint most likely vaporizes at 800° F. The mid-range infrared heat waves heat the paint and wood in 20-60 seconds only to 400-600º F. Therefore, dangerous lead fumes are not released from the heated paint.

                              I'm trying not to let my natural skeptic get the better of me, like @jtiers saying "Everyone knows that a lump of lead will jump off the table and poison you...." Both my grandpas were metalworkers in the 1920s-50s when guys were swimming in everything from asbestos to benzene. Both lived to around 80, one died of emphysema from smoking 3 packs a day for decades, the other of heart disease.
                              Sooo... You missed that bit where I said "as long as you don't get anywhere near the melting point you shouldn't have to worry about that" then?

                              And it does not matter a bit whether you breathe in a vapor (a metallic vapor would be particulate by the time it got into your lungs anyway) or fine particulates. They will both get trapped in the lungs and absorbed into the bloodstream.

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