Washing machine
The appliance that cleans everything else, and the one whose own cleaning problem has actually been measured. The contamination is not spread evenly, which changes what to do about it.
Precautions
- Disconnect from the power supply first
- Check the manufacturer's instructions
- Never mix with other cleaning products
In detail
A washing machine has an unusual property among the things here: somebody has counted. A peer-reviewed study sampled the two places machines are suspected of harbouring bacteria — the detergent drawer and the rubber door seal — and found both significantly contaminated, including potentially pathogenic species. The useful part is the distribution. The detergent chamber carried roughly four hundred times the load found on the TOP of the door seal, and the bottom of that same seal was contaminated while the top was not. That is a drainage result: water sits in the lower fold of a seal and in a drawer that never fully drains, and it is standing water rather than laundry the bacteria live in. The parts worth attention are the ones that stay wet. A home-hygiene review supplies the maintenance the study did not test. Biofilms build in machines run only at 30-40C on non-oxygen-bleach detergent. It asks for the drawer scrubbed WEEKLY, the seal wiped with weak bleach, the door and drawer left open to dry, and ONCE A WEEK OR EVERY FIFTH CYCLE a hot or disinfectant empty cycle — at the highest detergent level and longest time, because at low suds the water does not heat the interior enough.
Related
- Washing machine has the component Washing machine door seal
- Washing machine has the component Detergent drawer
- Washing machine has the component Washing machine drain filter
Hacks and claims involving this
- A hot empty wash cleans the machine Unresolved
- Leaving the washing machine door open Plausible mechanism, untested in this application
Sources for this page
Sources
Microorganisms (MDPI), 2021 · Scientific literature
Relied on for: That the detergent drawers and bottom door seals of domestic washing machines are significantly contaminated with cultivable bacteria including potentially pathogenic ones, and that the load differs by roughly two orders of magnitude between the detergent chamber and the top of the door seal. (states this directly)
Verification: a person has read the passage relied on.
Read on — The abstract and the conclusions. Supports the claim as stated.
Effectiveness of laundering processes used in domestic (home) settings
International Scientific Forum on Home Hygiene, 2013 · Scientific literature
Relied on for: That biofilms build up in machines run only at 30-40C with non-oxygen-bleach detergent and transfer to clothes, and its maintenance: weekly drawer cleaning, weak bleach on the rubber lining, door and drawer left open to dry, and a high-temperature or disinfectant empty cycle weekly or every fifth cycle at the highest detergent level and longest time. (states this directly)
Verification: a person has read the passage relied on.
Read on — Read to the end in Sprint 34. The Summary (pp. 5-6) and Appendix 1, 'Guidance on machine laundering of clothing and household linens in the home setting', with its endnotes (pp. 52-57), read in Sprint 31; the evidence review, sections 5 to 12 (pp. 7-51), read in Sprint 34. Supports the claim as stated. Sprint 31 took the guidance and left the evidence behind it unread; Sprint 34 read the rest and the guidance survived it, which is the useful outcome. Three things are now sourced rather than asserted: that an oxygen bleach product, not the dial, is what prevents transfer between items in a cool wash; that soiling degrades the wash enough to reverse it; and that machines miss their set temperature by up to 14C. It still publishes NO frequency, so the towel and tea-towel rows stay partial for the same reason as before.
What CleaningHQ cannot answer yet
These are recorded questions about this subject that we have not yet researched to a standard we would publish.
- Diagnose persistent odour in laundered textiles
- Softener residue as an appliance deposit
- Whether a duvet can be washed in a domestic machine
Last reviewed by a person on .