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Ammonia and Bleach
status student
age 20s
Question - I have two curiosities both concerning warning lables I
have seen. On the underside of a washing machine I read Do Not Mix
bleach and I believe ammonia or a nerve toxin would result, is this
true? The other states so not wash clothes soaked in vegetable oil
because they could spontaneously combust while being hung out to dry. I
thought spontaneous combustion was just a theory.
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QUESTION 1: NEVER mix chlorine-type and ammonia type cleaning and
bleaching products. Ammonia reacts with the hypochlorous acid in bleach to
form chloramines that have the general formula: NH2Cl, NHCl2, NCl3, and/or
Cl2 gas, depending on conditions and the ingredients of the cleaning
products. In a closed environment these compounds, even at low levels, are
powerful acute bronchial/lung irritants. The following website gives more
details: http://www.cdc.gov/mmwr/preview/mmwrhtml/00015111.htm
QUESTION 2: Maybe I'm missing something, but vegetable oil will be removed
effectively by most laundry detergent products. With regard to hanging
clothing out to dry, or even drying them in a hot air dryer, will not cause
them to explode, maybe more difficult to remove the veggie oil stain, but
not combust. I'm guessing that what is alluded to here is if you pile the
oil soaked clothing in anaerobic conditions, it is possible but not likely,
that spontaneous combustion could occur. Spontaneous combustion is the
result of the heat generated by either slow oxidation with/without oxygen in
an insulated combustible pile of combustible material.
It is not "a theory", it is a real effect, but it is not likely to occur in
a pile of laundry. You can experience this effect -- without the actual
fire -- by thrusting your hand into a pile of wet grass clipping that have
been in the sun for several days. You will experience that the center of the
pile of grass is significantly hotter than the surface where air convection
dissipates the heat. This heat is due to the decomposition of the grass
under the conditions described above. Laundry hung out on a line where there
is a lot of air circulation will not spontaneously ignite.
Vince Calder
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