/ Health, Home & Energy

Washing machines – does washing at 60 really banish bugs?

Washing machine

More than a third of Which? members use the 60°C program on their washing machine regularly. But is 60 the magic number when it comes to keeping bacteria at bay? And do washing machines actually reach 60°C?

We asked our members why they choose to wash at 60°C. More than half use this program to wash items like towels and bedding. These are laundry items that are typically associated with germs and for a long time the wisdom has been that we need to wash laundry at higher temperatures if we want to wipe out bacteria.

Normally, we test washing machines using 40°C programs, as modern washing detergents are effective enough to allow people to use 40ºC for almost all their washing needs. Towels and bedding seem to be the exception, due to the perceived advantages of washing at 60.

But can you rely on your washing machine to reach this temperature? And is 60°C actually high enough to kill bugs and bacteria anyway?

Testing top temperatures

We put 12 washing machines to the test and measured the top temperature they reached during a 60ºC  wash and how long that temperature was maintained. Eight of the machines did not get to 60 degrees at all. The lowest top temperature was 43°C.

Most of the machines kept the water cooler than 50°C for the majority of the program. That’s not exactly what you might expect if you’re using the 60°C wash with the hope of keeping your laundry bacteria-free.

Banishing the bugs

Our test results suggest that a typical 60°C wash can’t be relied upon to kill bacteria, especially if your machine only reaches this temperature for a couple of minutes (or not at all).

We asked a microbiologist for advice about ridding laundry of bugs and he explained that the real key to wiping out bacteria is using a good laundry detergent to wash them away. Detergents are much more effective than they used to be at lower temperatures, so even if your machine doesn’t get to 60°C, a good detergent can remove bacteria and viruses.

I very rarely use a 60°C wash at home. I prefer to be as energy and water efficient as I can and use a fast program that washes at 30°C. I used to wonder if I was taking any chances by not using a hotter wash on things like towels and sheets. Now I know that laundry detergent has a major role to play in bug removal as well as stain removal, I just have to always remember to actually put some in the detergent drawer…

Do you wash at 60°C? Which washing machine program gives you the most peace of mind when it comes to keeping your laundry bug-free?

Comments
Member

I generally use low-temperature washes because they are faster, less likely to damage clothes, and cheaper in terms of energy use. However I have been concerned about bacteria build-up/mould/slime in the machine.
Recently I had a very stained large white cotton cover for an armchair to clean, so I put it in on a very hot wash. To my horror it came out with lots of large grey/brown spots (some in a regular pattern, similar to the holes in the washing drum).
I can only conclude that using the hot wash on that rare occasion had dislodged lots of scum resident in the machine which had then deposited itself firmly on the fabric.
I have heard that it may be necessary to do lots of empty hot washes in a row to get rid of all this gunk – sounds expensive and troublesome! Any thoughts?

Member

Susanc – I think you are right and it is difficult to think of any other explanation of what you have seen.

Frequent maintenance washes are important when routinely washing at low temperature. Grease from our skin – maybe natural oils sounds better – builds up in the tub surrounding the clean shiny drum, and helps bacteria and moulds stick there and multiply. I am not convinced that doing a maintenance wash once a month is enough and I am not convinced that it is essential to run the machine empty. You might not have found out about the problem if you had run your machine empty. Without dismantling a washing machine it is difficult to know how clean the innards are.

Member

This has solved a mystery. I sent an evening dress shirt to the laundry for a premium-priced professional wash and ironing service. It wasn’t soiled but I was having the suit dry-cleaned and thought it worth having the shirt done properly as well and presented immaculately in a sealed cellophane enclosure for storage until needed again. After I brought it home and opened the brown paper wrappping I noticed that there were lots of off-white/greyish spots all over the front of the shirt. It didn’t occur to me at the time that they were in a sort of pattern. There was a note pinned to the shirt explaining that despite their best efforts the laundry couldn’t eradicate the stains on the shirt. I didn’t do anything more about it and just put it down to experience. I subsequently washed the shirt on its own in our machine on a 60 C cotton wash using Fairy non-bio gel with a small amount of fabric conditioner and ironed it myself while slightly damp [the shirt, I mean] and with a gentle spray-starch application. The results were at least as good as any laundry and the shirt looks perfect again. One never quite knows where dry cleaning services get the laundry done – it’s probably farmed out to local people on piece rates who, as one would expect, try to keep their costs down by generally using a low temperature setting. They might not pay much attention to the cleanliness of their washing machine believing that (a) frequent use takes care of any problems, and (b) this a 40 C wash is good for the environment. Once in a while they probably have to do a hot wash and, hey presto!, the clothes draw out the scum from the drum. I thank Susan C for explaining this.

Member
raj says:
29 March 2015

When the same happened to me I thought it was mould or mildew. In fact the drum bearing was broken and it was bearing grease. Do have that checked. I ruined quite a few shirts.

Member

Our machine did a perfect wash. The laundry service let us down and won’t get our custom again.

Member

Bearing grease seems a plausible cause for susanc’s problem. Bearings are usually sealed units but the space between the bearing and seal may be packed with grease. A washing machine engineer would know if this is the case.

Member

Susan if the marks on your cover after washing were greasy it could also be sign that the bearings are going on your machine, if it happens on other programmes as well.

Member

It is over 16 months since this problem of nominal 60C washes being far from that and Which? said it would be liaising with DEFRA. Perhaps we can have an up-date. The concept that fixed measurements like degrees C can be misused by manufactuers to meet EU plans is deeply troubling.

” 43°CThe hottest temperature reached by a Hoover washing machine on the 60˚C program

Instruction manuals must, however, contain wording stating that the temperature specified might not be reached. When we questioned all the manufacturers involved in our testing, they quoted this clause as the justification for not reaching 60˚C.
This means that the Hoover washing machine that only reaches 43˚C and gets an A+++ energy rating is acceptable under the current requirements of the EU label.

What is Which? doing about this?
The top temperatures reached by different machines in our tests varied by 24˚C. With no law requiring particular temperatures to be reached, manufacturers can, in theory, not heat the water as much to save on energy costs and improve their ratings.
As guidelines are currently so relaxed, we think the energy label is not a transparent and fair way to compare washing machines. Which? has contacted several organisations, including the Department for Environment, Food and Rural Affairs (Defra), which oversees the energy label in the UK.

Defra has confirmed that it will bring up this issue as part of the European Commission’s review of washing machine energy labels, so we’ll be meeting with Defra before that review to present our evidence.”

I am also ashamed to note that despite running this story the Which? website does not actually provide a button for dicovering which machines offer a hygiene wash – generally code for a more thorough wash with longer high temperatures and more rinse cycles. Given the huge rise in children suffering from allergies this would be useful. The 60C testing for washing machines also appears to be have been a one-off by Which? so consumers have no idea as to the actual temperatures reached in this cycle.