In pre-COVID-19 times, if there was any one area of cleaning that received more attention than all others combined, it was washroom hygiene. With so much focus already directed upon it — and with COVID-19 assumed to be an infection spread just by respiratory droplets — may be, there is no need to reassess the ways we clean bathrooms, right? Not really. Mrigank Warriar bares the truth of COVID-19 inside a washroom.
To start with it, is a misconception that COVID-19 transmission occurs only via the respiratory route. Researchers have found and isolated the virus from human stool; a subset of those infected have gastrointestinal upset as their main symptom, which can be explained by the less common, but no less alarming, faeco-oral route of transmission. Where is this likely to occur? Washrooms.
Flushing with the toilet lid open can spread COVID-19
Researchers at the Yangzhou University in China used computer modeling to study how water particles in the toilet bowl of two different types of toilets – single tank and double tank, or single-inlet and annular – behave after flushing. During the flushing process, water enters the bowl from a tank under the action of pressure and mixes with the water seal. This generates turbulence, which drives dramatic changes in airflow. They found that in both cases, a ‘toilet plume’ of particles is created, which can potentially infect the next bathroom user.
This plume of possibly virus-laden particles emerges at high speed; 40-60% of the total number of particles may rise above the level of the bowl to cause large area spread, upto a height of over a metre.
Seventy seconds after a single-inlet flush, around 2,700 particles have been sprayed up from the surface of the toilet bowl, the study said. Given the same amount of water and the same gravitational potential energy, annular flushing causes more virus spread; around 1,511 particles can escape within 35 seconds of flushing.
One can foresee that the velocity will be even higher when a toilet is used frequently, such as in the case of an office toilet during a busy time or a public toilet serving a densely populated area.
How can this be prevented?
- Put the toilet lid down before flushing.
- Clean the toilet seat before using it, since floating virus particles could have settled on its surface.
- Wash hands carefully after flushing, since virus particles may be present on the flush button and door handle.
- Waterless flushing has the potential to reduce the risk of pathogen transmission because it can create a physical barrier between faeces and the user by sealing the faeces.
- Install more better-designed toilets in which the lid is automatically put down before flushing and cleaned before and after flushing.
How should a toilet be cleaned in the times of COVID-19?
According to the characteristics of fecal–oral transmission, there will be a large amount of virus particles within a toilet when a confirmed case of COVID-19 uses it. Thus, toilets should be regarded as one of the sources of infection, and cleaned accordingly.
Family Welfare recommends cleaning the bowl itself with a long-handled angular brush, and other surfaces with a nylon scrubber using freshly prepared 1% sodium hypochlorite. Seventy percent alcohol can be used to wipe down surfaces where the use of bleach is not suitable, e.g. metal. Chloroxylenol (4.5-5.5%)/ Benzalkonium Chloride or any other disinfectants found to be effective against coronavirus may be used as per manufacturer’s instructions.
It also advises against using disinfectant sprays on potentially highly contaminated areas (such as toilet bowl or surrounding surfaces) as it may create splashes which can further spread the virus.
The Finnish Institute of Occupational Health has listed the following step-by-step instructions:
- Wear disposable protective gloves whenever you clean a toilet.
- When you clean a toilet bowl, wear long protective gloves that go up to your elbow on top of the disposable gloves and clean the long gloves with a disinfectant afterwards. The long gloves must have a designated container in the cleaning cart from which the gloves can be put on easily without touching the outer surface of the gloves, except for the opening. Put the disposable gloves worn underneath the long gloves in a waste bin after you have cleaned the toilet
- Apply a small dose of the detergent on the toilet bowl, on both sides of the lid and on the seat. Close the lid of the toilet and flush the toilet.
- Apply the toilet bowl cleaner on the bowl and its vertical surfaces while paying special attention to stains. Put on the long cleaning gloves. Clean the bowl with a toilet brush. Wash the brush when you flush the toilet and close the lid. Clean the outer surfaces of the bowl and any stains on the wall with a cloth.
- When you exit the toilet, do not touch the door handle or use a paper towel to open the door.
Recommended cleaning order of the toilet bowl:
- Water tank and its knob, and swivel of cleaning cloth
- Top cover and swivel of cloth
- Seat ring and swivel of cloth
- Lower toilet seat.
Apart from toilets, what are the other areas needing attention in shared washrooms?
The floor, sinks, shower area, taps, soap dispensers, door handles and dustbins in washrooms can all harbour the virus on their surfaces. In the hotel segment, hair dryers, electric toothbrushes, shavers or other appliances in the bathroom also need to be cleaned. Outside of the human body, the longest viability of the virus is on stainless steel and plastic; the estimated median half-life of COVID-19 is approximately 5.6 hours on stainless steel and 6.8 hours on plastic.
Design features to help reduce the risk of COVID- 19 transmission in shared washrooms
- Backflow valves on sprayers and faucets to prevent aerosolized faecal matter from entering the plumbing or ventilation system
- Functioning hand-washing facilities with water and soap should be available within 5 metres of all toilets, both public and private, as recommended by WHO
- Turning the tap on/off: either a sensor, foot pump, or large handle may be used, so the tap can be turned off with the arm or elbow
- For liquid soap, either a sensor-controlled dispenser or one large enough to be operated with the lower arm
- If using a bar of soap, the soap dish should be well-drained, so the soap doesn’t get soggy
- Phase out blow dryers, since they can generate aerosol. Provide paper towels, or encourage air-drying
- In traditional basins, users wash their hands and then move away to another area where the tissue paper is kept. Avoid this by providing paper towels next to each basin
- Use smart washrooms: A common complaint among users concerns consumables such as soap and toilet rolls running out well before replacements are at hand. In smart washrooms, when refills are required, sensors in the dispensers quickly alert cleaning crews about the impending need. As a result, no user is caught in a situation where s/he is unable to wash or wipe hands as a particular product has run out and not been replaced
- Temporarily block alternate sinks and urinals in rotation, to ensure physical distancing
- Bathroom attendant needs to also monitor and restrict the number of people inside a washroom at any given time
Toilet cleaning SOP
- Avoid unnecessary touching of Doors, knobs and handles. The same to be sanitized hourly basis.
- Janitor to wear PPE before entering the washroom.
- All doors, knobs and handles to be cleaned with microfiber dusters and disinfectant. (To be maintained hourly – high footfall area)
- Cleaning of all switches and boards with disinfectant.
- Vertical surfaces cleaning with disinfectant.
- Cleaning of mirrors with glass kit and disinfectant.
- Cleaning of all taps, flush,faucets and accessories. (Tobe maintained hourly withdisinfectant and microfiberduster)
- Cleaning of soap and tissue dispensers with disinfectant. (To be maintained hourly – high footfall area)
- Cleaning of washbasin and platform with disinfectant. (To be maintained hourly – high footfall area)
- Cleaning of urinal pot, WC and seat cover with disinfectant. (To be maintained hourly – high footfall area)
- Floor scrubbing with disinfectant and steam cleaner/scrubber machine. (To be maintained hourly by wet mopping and disinfectant)
Picture Courtesy: Forbes Facility