Last reviewed 1 June 2020

Within a relatively short space of time, the coronavirus has radically changed working life around the world, perhaps forever in the case of some organisations. Never before has workplace cleaning taken on life and death implications across so many different types of ordinary, non-specialist, work settings. Vicky Powell looks at how to deep clean workplaces to best protect workers and others from the COVID-19 virus.

A new approach to cleaning workplaces

There have always been workplaces when good hygiene is, quite simply, a matter of life and death. Nurses and doctors understand full well the importance of scrupulously clean, disinfected operating theatres. Likewise, food safety experts have long emphasised the importance of caterers and other food industry workers being sure to diligently cleanse fresh produce and sanitise kitchen working surfaces and other equipment.

In the current occupational climate, however, we are seeing an unprecedented focus from Government health experts and their medical advisors on the importance of decontaminating the widest range of ordinary workplaces where there has been the risk of contact with a person who has carried the coronavirus (or COVID-19).

Understanding deep cleaning

It should be noted that deep cleaning isn’t really a scientific term as such. The latest UK Government advice updated in May 2020 by Public Health England (PHE) refers simply to the “cleaning” of workplaces and working areas which may have been contaminated by the COVID-19 virus. The new guidance, specifically written in the context of COVID-19, has been published using the health authorities’ experiences of other viruses within the corona family, such as SARS and MERS, and will no doubt be updated as more is discovered about the virus.

It may, firstly, be useful to distinguish between cleaning and disinfecting, in the context of the coronavirus, as explained by the USA’s Centre for Disease Control and Prevention (CDC) guidance.

  • Cleaning refers to the removal of germs, dirt and impurities from surfaces. It does not kill germs, but by removing them, it lowers their numbers and the risk of spreading infection.

  • Disinfecting refers to using chemicals, ie suitable disinfectants, to kill germs on surfaces. This process does not necessarily clean dirty surfaces or remove germs, but by killing germs on a surface after cleaning, it can further lower the risk of spreading infection.

Types of workplaces that may need deep cleaning

Any kind of workplace might need deep cleaning if there has been the risk of contact with someone with COVID-19 and, of course, there are specialist guidelines for healthcare settings such as hospital wards and operating theatres.

The new advice from PHE however focuses on non-healthcare environments which could include settings such as:

  • offices and other workplaces

  • waiting rooms

  • hotel rooms

  • student accommodation

  • boarding schools.

What you need to know

Some important starting points for cleaning workplaces to reduce the risk of the spread of coronavirus, according to the current PHE guidance, are as follows.

  • The amount of virus living on surfaces will reduce significantly after 72 hours. If a workplace area can be kept closed and secure, wait until this time has passed before cleaning.

  • Wherever possible, wear disposable or washing-up gloves and aprons for cleaning. This is the minimum personal protective equipment (PPE) to be worn for cleaning a workplace area where a person with possible or confirmed COVID-19 has been. These should then be double-bagged, stored securely for 72 hours and then thrown away in the regular rubbish after cleaning is finished. (See Handling Rubbish Bags below for further information about possible COVID-19 contaminated waste.)

  • Using a disposable cloth, first clean hard surfaces with warm soapy water. Then disinfect these surfaces with the products you normally use, ie household disinfectant, according to current guidance. (This should contain the 1000 parts per million (ppm) available chlorine recommended in the latest PHE guidance.) Pay particular attention to frequently touched areas and surfaces, such as bathrooms, grab-rails in corridors and stairwells and door handles.

  • Avoid creating splashes and spray when cleaning.

  • Wash hands regularly with soap and water for 20 seconds. After all PPE has been removed, ie after taking off gloves, aprons and other protection used while cleaning, wash hands with soap and water for 20 seconds.

Remember: wiping down an area with normal household disinfectant (see Further points about cleaning and disinfecting below) after someone with suspected COVID-19 has left will reduce the risk of passing the infection on to other people.

What to do where the risk of COVID-19 is higher

If a risk assessment indicates that a higher level of virus may be present, eg where unwell people have slept in a hotel room or boarding school dormitory or if an area has been heavily contaminated, such as with visible bodily fluids from a person with coronavirus, then additional PPE is recommended to protect the cleaner’s eyes, mouth and nose (as well as wearing gloves and an apron). PHE says that its local Health Protection Teams can advise on these sort of situations.

All surfaces that a symptomatic person has come into contact with must be cleaned and disinfected, including:

  • objects which are visibly contaminated with body fluids

  • all potentially contaminated high-contact areas such as bathrooms, door handles, telephones, grab-rails in corridors and stairwells.

In addition, the PHE guidance recommends that any items that are heavily contaminated with body fluids and cannot be cleaned should be disposed of.

Further points about cleaning and disinfecting

The PHE recommends using disposable cloths or paper roll to wipe down all hard surfaces, chairs, door handles and sanitary fittings, and using disposable mop heads for the floors, following one of the two options below.

  1. Cleaning with a household detergent, followed by a wipe down with disinfectant (the current PHE guidance specifies using a disinfectant with 1000ppm available chlorine and, as mentioned above, guidelines suggest a disinfectant solution made up of 20ml (4 teaspoons) of household bleach in 1000ml (4 cups) of water) would be suitable.

  2. A combined detergent disinfectant solution at a dilution of 1000ppm available chlorine (you would need to check the specific detergent disinfectant solution for details).

It is important to follow the manufacturer’s instructions for dilution, application and contact times for all detergents and disinfectants.

In addition, it is important to take note of the following.

  • Public areas where a symptomatic individual has passed through and spent minimal time, such as corridors, and which are not visibly contaminated with body fluids can simply be cleaned thoroughly as normal.

  • Any cloths and mop heads used should be disposed of and put into waste bags as outlined below.

  • The PHE suggests using steam cleaning when items cannot be cleaned using detergents or laundered, eg in the case of upholstered furniture and mattresses.

What about laundry?

The PHE suggests washing items in accordance with the manufacturer’s instructions but using the warmest water setting and drying items completely. Dirty laundry that has been in contact with an unwell person can be washed with other people’s items, according to the guidance.

However, cleaners should be trained not to shake out dirty laundry, in order to minimise the possibility of dispersing virus through the air.

Anything used for transporting laundry with the company’s usual products, should be cleaned and disinfected in line with the latest PHE cleaning guidance.

Handling rubbish bags

The PHE recommends that waste from possible cases and from the cleaning of areas where possible cases have been (including disposable cloths and tissues) should be put in a plastic rubbish bag and tied when full. The plastic bag should then be placed in a second bin bag and tied.

Next, the bag should be put in a suitable and secure place and marked for storage until the individual’s test results are known.

If the individual tests negative, this can be put in with the normal waste. If the individual tests positive, then store it for at least 72 hours and put in with the normal waste.

If storage for at least 72 hours is not appropriate, PHE says to arrange for collection as a “Category B infectious waste” either by your local waste collection authority if they currently collect your waste or otherwise by a specialist clinical waste contractor. They will supply you with orange clinical waste bags for you to place the bags into so the waste can be sent for appropriate treatment.

Finally, waste should be stored safely and kept away from children. Waste should not be put in communal waste areas until negative test results are known or the waste has been stored for at least 72 hours.

A word about home working and the pace of change

At a time when millions of British employees are working from home, with homes having become the new global workplace practically overnight, the above principles can usefully be applied to home offices too.

However, the COVID-19 situation is fast-changing and unprecedented. Scientists’ work with COVID-19 is, at the time of writing, ongoing and so it is important to check Government guidance regularly for any changes and keep up to date with expert advice on the subject.