What do you do when you flush? Covid-19

Lid up or down?

When you flush the toilet in the bathroom the process creates a fine aerosol of droplets which spread and linger in the air around the toilet. Closing the lid of the toilet reduces the dispersion of this fine mist, it reduces the spray which may contain fecal matter. That fecal matter can transmit the Covid-19 virus (and other bugs such as e-coli) and transfer it to other surrounding surfaces.

In the case of our holiday cottage that contamination from the toilet could settle on the shower enclosure, the bathroom floor, the wash basin and taps (faucets).  It is why we always wipe down such surfaces during end of rental turnaround cleaning. We have to assume our guests are not biosecure in their daily habits. Typically we'll use Zoflora in water. (1:30 concentration) and leave the surface damp for at least 5 minutes to allow the biocide to work.

Here's what the active biocide in Zoflora does to rats during tests.

Using a Fogger to disinfect the cottage?

Having seen the advice from the rental agency Sykes to use fogging, or ULV machines, to disinfect the holiday cottage I thought some investigation is in order before exposing our guests to these substances.  Here's one substance a local business is recommending as a biocide suitable to destroy Covid-19. It is called Vanoquat, it is used in animal husbandry and the food processing industry.   

Used as 1:25 dilution with water it is loaded into a fogging machine and you need about 3 litres of the solution in 100 Cubic metres. Our one bedroom cottage is about 75 Cu M, so we'd need around 2.5 litres sprayed around, as part of a two stage cleaning programme, so wash down surfaces first with detergent and water.  The instructions are lacking information about how soft furnishings should be treated, but you don't often get soft furnishings in cattle barns.

According to the local contractor, you then leave the treated area for at least 90 minutes. Again, there's no advice is the distributors safety documentation about how long should be left before human occupation in the area.

The chemical can cause permanent eye damage, it should not come into contact with the skin and the mist should not be inhaled. So the recommended PPE is waterproof boots, full body covering with waterproof suiting, rubber gloves on hands, eye and face protection. The safety sheet says no respiratory protection is required, but elsewhere advised not to breathe the mist, so I'm guessing a suitable respirator may be appropriate. Certainly all the videos I've seen, the fogger operatives are wearing respirators to protect against the mist.

If I was a guest in the cottage, I wouldn't want to sleep in that environment. There are some less toxic cleaning fluids, but they make no mention of application by fogging. In a Premier Inn customer assurance video they show their staff using a single stage (combined detergent/biocide) from hand spray bottles but only hard surfaces are treated.  The Covid-19 virus remains viable for a few days on soft surfaces.

We've chosen to use Ultraviolet lamps and superheated steam (using de-ionised water) to supplement a cleaning programme.

Here's the advice from the World Health Organisation:

In indoor spaces, routine application of disinfectants to environmental surfaces by spraying or fogging (also known as fumigation or misting) is not recommended for COVID19. One study has shown that spraying as a primary disinfection strategy is ineffective in removing contaminants outside of direct spray zones.

Moreover, spraying disinfectants can result in risks to the eyes, respiratory or skin
irritation and the resulting health effects.

Spraying or fogging of certain chemicals, such as formaldehyde, chlorine based agents or quaternary ammonium compounds, is not recommended due to adverse health effects on workers in facilities where these methods have been utilized.

Spraying environmental surfaces in both health-care and non-health care settings such as patient households with disinfectants may not be effective in removing organic material and may miss surfaces shielded by objects, folded fabrics or surfaces with intricate designs. If disinfectants are to be applied, this should be done with a cloth or wipe that has been soaked in disinfectant.

Other sources:
https://pubmed.ncbi.nlm.nih.gov/25812396/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4260154/
https://aem.asm.org/content/70/6/3449



Edit: 26/06/2020

Some people are recommending the use of dilute Hypochlorous acid in foggers. A common way to manufacture this is by electrolysis of dilute salty water (Sodium Chloride) and indeed you can buy devices which make small quantities of dilute Hypochlorous acid.  The electrolysis produces Chlorine and Hydrogen; the Chlorine gas produced (in small quantities)  dissolves in water to form hypochlorous acid. Electrolysis of brine is the commercial process used to manufacture sodium hypochlorite bleach, i.e. the common household bleach.  It is known that breathing in bleach vapour damages the lungs. Common Bleach also contains sodium hydroxide, i.e. Caustic Soda arising from the electrolysis process.

The manufacturers of hypochlorous fogging machines that hypochlorous acid is produced naturally by the body as a defence against infection. No doubt it is, in minute quantities at a cellular level, but the body also produces quite a lot of hydrochloric acid in the stomach as part of the digestive process. In the wrong place in the body hydrochloric acid would do a lot of damage. Remember the burning pain of acid reflux in your throat?

Cleaning the cottage in a Covid Era

We just received guidance from the Rental Agency (Sykes) on the health measures needed when the holiday cottage industry opens again. Their current conclusions:

• Provide PPE for cleaners or changeover staff; disposable gloves, aprons, masks, hand sanitiser.
• Clean most surfaces with bleach/disinfectant
• ULV Fogging machine used in all rooms between bookings; 
• Change all cleaning cloths, mops, oven gloves, bathmats, tea towels and towels between bookings;
• Change all linen, bagged before laundry;
• Change pillow and mattress protectors between bookings;
• Change gloves between each stage of cleaning;
• Clean high use areas, also ovens, fridges, freezers,toasters, kettles, irons, hair dryers, and vacuum cleaners, bathroom fittings
• Clean controls, books, toys, games
• Clean bins inside and out; empty bins between bookings (note the council only collect fortnightly).
• Clean umbrellas, mops, dustpan & brush and brooms
• Clean garden furniture, Bbq, Sheds, Garages, shared entrances, key safes.
• In  addition to soap, supply guests with disinfectant, hand sanitiser, tissues, disposable gloves, new cloths (?), disposable wipes, paper towels; i.e. throw away the  unused toilet rolls and paper kitchen rolls after a guest stay.

Note that fogging machines cost around £500 or more, if you ignore the cheaper (unwarranted and uncertified) Chinese Ebay type of device. Their recommendations would also entail expenditure on additional bed and bathroom linen from the current four sets to six sets of linen and towels. The additional cleaning will increase the man hours needed for change over. 


We recently had to do an extensive deep clean when some guests decided to smoke  inside the property, against the booking conditions, during their stay. It greatly increased the cleaning time from about ninety minutes to five hours work. I'd imagine doing extensive anti-virus cleaning will see similar extensions.

So far Sykes haven't explained how this additional expenditure will be recouped, they certainly they  haven't suggested they'll contribute to the costs. As we currently only make on average £3 profit per day this additional funding will have to come from increased rental charges. The ownership of Sykes changed hands from private equity company Livingbridge for $480 Million USD in the autumn of 2019 and have a reported annual profit in the region of $25 Million USD.

Discussions are ongoing but their initial idea was for us as owners to offer a 20% discount on rental to prospective clients to encourage bookings. It seems like a recipe to increase losses in the face of increased cleaning costs and extended between stay gaps.

We've also done some research:

• https://www.bbc.co.uk/news/uk-scotland-scotland-business-52577705
• https://www.cdc.gov/coronavirus/2019-ncov/community/disinfecting-building-facility.html
• https://www.aftermath.com/blog/the-truth-behind-fogging-cdc-recommended-cleaning-and-disinfection-procedures-for-covid-19/
• http://www.iuva.org/IUVA-Fact-Sheet-on-UV-Disinfection-for-COVID-19
• https://www.pascuk.co.uk/standards
• https://www.independentcottages.co.uk/holiday-blog/coronavirus-considerations-for-reopening-your-holiday-home-to-guests

Edit 02/06/2020: Added details of Sykes

Fake UV-C germicidal lamp from China

Earlier I mentioned how we are investigating the use of Ultraviolet lights to sterilize the holiday cottage after a guest stay in these times of Covid-19. I purchased via Ebay a 60W Corncob "UV-C" lamp based on UV-C LED technology. It was despatched from China. Little did I realise that it was a fake, and while it produces a bright blue light there is little UV-C light output by the device. This makes it useless as a biocidal lamp.

This is a picture of the lamp I purchased:

I was alerted to the possibility of the fake, by this Youtube video:

I'm in dialogue with the Ebay vendor to assess their reaction. So far all they have claimed is that the have a CE certificate, with no offer of a refund.  The image they sent me was of a certificate issued in China about two weeks after the date of my purchase. On investigation the tests performed by the laboratory in China relate only to electromagnetic interference with other devices and the level of "flicker". The CE test did not measure the UV-C output from the lamp.  I am arranging for my lamp to be tested against a laboratory UV-C light meter. At a cost of £850 these meters are not cheap, and finding a company to perform the test was a challenge, but I am expecting to receive the results in a couple of weeks..

Here's an expert view on using UV-C for disinfection: http://www.iuva.org/IUVA-Fact-Sheet-on-UV-Disinfection-for-COVID-19 

and a different Youtube lecture  https://www.youtube.com/watch?v=uqSHPKicIbs

Edit: 25/06/2020

Amazon introduce a campaign against counterfeits, unfortunately this will not guard against products that make fake claims about their capabilities such as these "LED UV-C" lamps. Their measures only relate to protecting trade marked original goods. I eventually purchased a genuine UV-C Lamp from a UK supplier, details here.

Edit: 01/07/20

We've had the results back from the laboratory.  From the fake corncob lamp the UV-C reading is 7 microwatts/Sq Cm (254 nm UV) at a measured distance of 5 cm from the bulb. From a comparative "daylight white " 5 watt LED domestic bulb the same 7 microwatts/Sq Cm. In other words the fake UV-C corncob lamp has no more disinfecting power than a normal LED bulb.

By way of comparison a 73W mercury vapour UV-C germicidal lamp gave a reading of 7.17 milliwatts/sq cm measured at the same distance from the lamp surface. It is about 1000 times more powerful.

Edit 10/07/20

The vendor has disappeared from Ebay; though these fakes are still on sale on both Ebay and Amazon.  I've reported a few cases but Ebay and Amazon do not appear to be interested.

Using secondhand VoIP phones

As part of our work to support the local Covid-19 support group we are lending VoIP phone handsets to some of the organisers. The handsets are programmed to use the special range of distinctive numbers allocated by us to the team. To ensure good quality voice on the phone we are using Polycom desktop handsets, these are business quality devices designed for office use.  Once programmed by us, it should be just a matter of plugging the devices into the the RJ45 LAN outlet on the broadband router in the home and, after power is supplied, the devices automatically connected to the Sipgate service. The organiser team then obtain the full facilities of a distributed office PABX in their own home. It also protects the personal phone numbers of the organisers from general public exposure. There always are some weirdo's who would want to exploit personal phone numbers.

When purchased new, these handset have a price of circa £75 - £100 as they have quite powerful micro computers embedded in the device. In order to keep costs down we've purchased secondhand units from Ebay. These are fully functional older units no longer required by businesses, but look like new devices. They cost less than £20 to purchase including delivery.  The particular model we are purchasing have dual power options. You can either buyer dedicated mains power supply units delivering 24V, or they can use PoE (Power over Ethernet cable) which has power delivered via the network cable. The PoE option greatly tidies the cabling associated with using the phone, all that is needed is a single CAT5e network cable plus, in the home environment, a power injector unit close to the Broadband Router.

When used in conjunction with the Sipgate web browser interface you get "click and call" facilities from the VoIP phone with no need to dial the phone number via the handset keypad. You just click on the number and your handset rings. As soon as you pick up the phone handset, or press the speakerphone button, Sipgate will connect the call.

Well, that's all of the theory, now for the practice. When we received the secondhand devices, we found the units still had their programming from their previous owners. Some the previous programming was quite specialised. Normal configuration programming by us did not allow the phones to function correctly and connect to Sipgate. After a lot of research, we realised we had to completely wipe the memory on the phones, not just a standard "factory reset", we had to reformat the memory using a well hidden function on the phones. We then set up a FTP software server to hold the appropriate historic version of the software and basic configuration files. We were able to track the software and files down on the Polycom support website. It took quite a lot of Google research and the downloading of multipage administrator manual pdf files. Normally telecoms engineers go on training courses to learn these processes, we didn't have that luxury and spent about five hours hard work and experimentation to getting it done. Now the phone automatically visit the servers via the Internet, to pick up the latest configuration when they are powered up or restarted.

However once we'd "cleaned" the handset memory and reloaded the phones with new copies of the software they work just fine. Now that we understand the process, it is quick and easy to remotely program the handsets. It was time well spent. We're about to handover the devices to the volunteers, plus network cables and power units, all suitably sterilized with isopropyl-alcohol wipedown and exposure to UV-C disinfection lamp. 

We already use VoIP phones in the holiday cottage, but there we'd installed a brand new handset so we didn't have any configuration problems.

Edit: 21st April 2020
The only remaining problem is get the recipients of these VoIP handset to plug them in and to use them  So far the reprogrammed handsets have not been connected following delivery. There are no reported problems.

Edit: 26th April
The recipients of the VoIP phone have called in an engineer to sort out network problems in their own home.

Doing our bit for Wirksworth

We don't live in Wirksworth, but we do own a holiday cottage here, so we do feel some sense of community with the people whose homes are in the town. We live just eight miles down the road in Belper.  To keep in touch with what's happening I keep an eye on the main Wirksworth Facebook group. I noticed a local group had formed to coordinate volunteers to help others during the Covid-19 outbreak. They were looking for people to help with their phone communications. By sheer luck I've a lot of experience of setting up Information Technology Infrastructure for large organisations around the globe. Part of that work used to involve supervising the provision of office phone systems, so while I'm not a telecoms engineer I do have some depth of understanding of the capabilities of the technology. I've also set up telephone systems for my own company during major projects.

Over in Belper, a couple of weeks previously, I'd helped the local Covid-19 Mutual Aid Group by setting up a phone system complete with voicemail for them, including a distinctive easily remembered contact phone number I'd acquired a couple of years ago for the cottage.  The system made life a lot easier for the Belper organisers who had previously struggled with just three mobile phones.

I made contact with the organisers of the Wirksworth Group, and after some discussion about their requirements set up a similar phone system for the team. It provides seven phone lines, each with distinctive phone numbers, a central help line (01629 888112), a voicemail system and the ability to redirect calls at a moment's notice. The whole process took just a few days to become operational, including me giving some training sessions by video conference. It is relatively low cost and can be easily expanded or contracted at short notice. Their system is based around Sipgate.

UV-C Sterilising Holiday Cottage

Our rental holiday cottage is closed at the moment due to the Government legislation to reduce the spread of Covid-19 infection. So no bookings are being accepted by Sykes. We've been planning for when bookings are once again allowed. Holiday makers will no doubt be nervous about using premises that will have been used by strangers just a few hours before. We'll be planning on having a minimum of a one day gap between bookings. This will give us the chance to give the property a good wipe down with  good disinfectants. We're also purchasing an Ultraviolet lamp (UV-C) to help sanitise the property. 

We've had one on order from China for some weeks now and a package arrived a few days ago. Unfortunately they sent the wrong device, a small USB 5 watt lamp, which is not suitable for sterilizing rooms. We've reordered an even more powerful lamp. This one will be 60w and should be able to treat each room in less than an hour, though we'll need to ventilate the rooms for a few hours to vent the ozone produced by the lamp.  We've already purchased some UV-C safety goggles as this light can severely damage unprotected eyes.

Edit: 26 April 2020

The re-ordered bulb has arrived and is undergoing trials (it turns out to be a fake, see below). It has multiple small UV-C LED chips on it's surface giving a total of 60W (230 VAC) of light.The cost including shipping was less than £30. In terms of electric lighting it is very bright and powerful, given that normally we might have only 4 x 5 watt LED bulbs lighting a room. The UV-C lamp we've obtained has a remote control switch which makes it a lot easier to use safely, but we always wear protective goggles if power is connected to the unit even if the lamp itself is "switched off".  It is a very easy way to sterilise keyboards and mobile phones without causing damage.

Combining UV-C lamp with wiping down key surfaces with disinfectant, we should be able to make our cottage safe for new guests within a couple of hours. According to the manual it only needs 15 minutes exposure in a room, but we take 2 or 3 sessions with the lamp located in different positions to avoid shadows.

Edit: 20 May 2020

It turns out the 60W UV-C light is a fake and produces no UV-C light. The classic Chinese supplier using Ebay to distribute goods. We're still investigating, so more on this later.

Edit 26 June 2020

We found a genuine UV-C lamp with a UK supplier. Details here.

Edit 6th July 2020
We now have a proper UV-C meter to check exposure levels. Details here.

Edit 25th July 2020
We've located and ordered some UV-C dosimeter labels to help us check the correct ultraviolet treatment has been delivered to the rooms.