I work in a car dealership, and the guy who cleans the workshop uses an industrial floor scrubber / vac on the floor tiles. On particularly stubborn oil / soot marks, he uses naphtha-based brake cleaner in a spray dispenser as almost a "pre-wash", and then goes over it with the scrubber.

If the machine has been left for a while, perhaps for over a week during the holidays, the machine produces an acrid, pungent smell that burns the eyes and back of the throat. Almost like bad drain-type smell, and he thinks its just stale water, and we're being wusses — but the odour goes around the whole building, and my proximity to the workshop means I get a good dose of the terrible smell.

I have a theory that the brake cleaner is having a reaction with the detergent in the machines waste tank, and when he starts it after it has been festering. It's really bad, and what's more, I think it is hazardous.

The two chemicals are: a naphtha-based brake cleaner, and an industrial floor cleaner containing things such as 2-(2-butoxyethoxy)ethanol, isotridecanol ethoxylate etc. I can provide more details from the safety data sheets if wanted, but is the above enough to make a forward conclusion?

  • 2
    $\begingroup$ These situations are pretty tough to get to the bottom of. Most of the substances probably don't have long term health studies. On the other hand, the burning sensation is telling. I suspect you're not going to get a lot of traction on this topic, but maybe you can just circumvent the whole issue by checking to see if they can improve the ventilation in the workshop and just flush everything out. $\endgroup$
    – Zhe
    May 18, 2022 at 14:19
  • $\begingroup$ The floor-cleaner is meant for large-scale application, and likely has been tested to meet OSHA and other standards, but brake-cleaner is usually used in only a limited area, and in well-ventilated spaces. Check its ingredients, particularly for more toxic chemicals than naphtha, e.g., chlorinated solvents or aromatic compounds such as toluene or xylene. $\endgroup$ May 20, 2022 at 2:38

1 Answer 1


Normally, surfactans (like the ethoxylated alcohols you referenced) are relatively stable under various conditions. I'd worry a bit about the hydrocarbon exposure by itself; in the long run, your brain is not going to be all too happy if exposed over longer periods of time in a badly ventilated setting.

bad drain-type smell

That would trigger me towards dihydrogensulfide formation. Even with the MSDS at hand, it can be hard to tell if you run that risk, e.g. because of him accidentally mixing an acidic cleaning product with a sulfur compound-containing product.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.