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In 2020 we have a new pandemic
labelled COVID-19.

COVID-19 is an acronym for Corona Virus Disease (Covid) 2019. It is an infectious disease caused by a new (novel) coronavirus (nCoV). The virus gets its name because of its crown (corona) like appearance. COVID-19 is an enveloped virus, in which the envelope comes from the host cell. This envelop helps the virus survive and infect other cells. Unlike bacteria, viruses can’t replicate outside of a human host. SARS-CoV-2 utilizes the host cells to replicate its DNA.

Susceptibility to Disinfectants

Enveloped viruses like SARS-CoV-2 are very susceptible to disinfectants, influenza being one of them. This means it is much easier to inactivate than other diseases like norovirus.

There are numerous emerging studies on coronaviruses, specifically SARS-COV-2 (COVID-19). Many have varying claims under laboratory conditions

One early study, called “Persistence of coronaviruses on inanimate surfaces and their inactivation with biocidal agents”, published in February 2020 in the Journal of Hospital Infection, lists the following:

“…human coronaviruses such as Severe Acute Respiratory Syndrome (SARS) coronavirus, Middle East Respiratory Syndrome (MERS) coronavirus or endemic human coronaviruses (HCoV) can persist on inanimate surfaces like metal, glass or plastic for up to 9 days,…”

”but can be efficiently inactivated by surface disinfection procedures with 62–71% ethanol, 0.5% hydrogen peroxide or 0.1% sodium hypochlorite within 1 minute.”

These concentrations support some manufacturer claims. Generally we can have confidence that a disinfectant, at these concentrations, will work.

Disinfection and Contact Time

  • A disinfectant will include claims for a significant spectrum of viruses, bacteria, fungi etc.
  • The contact time for each specific virus or bacteria could be different as some are killed faster than others
  • When we apply the disinfectant for the “contact time” we are indicating that all pathogens on the list will be inactivated

Terms and Definitions

While explaining our services to facilities, there are certain terminology that are encouraged:

Affected Zone – refers to the zone identified by the client that likely contains the highest surface concentration of viruses because of trace contacting the infected persons’ access to the facility.

Trace Contacting – the process of reverse tracing the flow and access of the affected person within the facility with the objective of identifying high-priority touch points.

Touch Point – any area that is touched frequently and can be a potential vehicle for the transmission of viral pathogens.

Four levels of “clean”

Based on what kind of “clean” you are going for, you will want to re-assess your chemical inventory and applications.

Other Considerations:

  • You should select disinfectants that are readily available or are from a local supplier
  • You should use chemicals that have a DIN number, are on the EPA list, the Health Canada List, or that have an active ingredient concentration set out by the CDC.
  • Check government lists often, as they are constantly updated
  • You need to balance the need for high grade disinfectants against facility need and/or occupancy factors

Consider the following:

  • Some disinfectants have strong odors
  • They may lead to skin sensitivity or irritation in staff occupied areas
  • The level of disinfection may be excessive (e.g the disinfectant is suited for healthcare)

Frequency of Cleaning

To determine how often you need to clean a touch point surface, a two-step process is required.

Risk Assessment

The Risk Stratification Matrix

You should quantify risk to avoid subjectivity

Risk assessment should be done by a person who:

  • Is familiar with the facility
  • Is knowledgeable on occupancy levels within the area
  • Understands visitor/personnel flow within the building e.g elevator use, congregation areas etc.
  • Has general knowledge of types of visitors e.g. seniors, immune compromised
  • Is knowledgeable about “travel times” and has a relationship with the cleaning service provider
  • Is a landlord, facility manager, property manager etc.

Consider site specific factors

  • Travel Times
  • Productivity per square foot
  • Opening and Closing Times
  • Busy Periods and Holidays
  • Types of services and occupants
  • Resource allocation and budgets
  • Engineers controls in place

Scope of Work Modification

Based on your frequency of cleaning determinations, you should modify your scope of work. This will include contacting your service provider to involve them in planning. Your facility should direct scope based on “risk and resources” in order to prevent excessive recommendations. An important thing to do is to apply a resource calculation to determine whether your proposed frequency of cleaning is feasible so you can set realistic expectations (don’t expect one custodian to sanitize every entrance, every 15 minutes, if it takes 20 minutes to walk from one end of the building to another). This means setting aside resources appropriately for what jobs you expect to be done.

Validation of Cleaning Frequency

Some ways you can show occupants that a building has been cleaned and when are:

  • Increase visibility of cleaners through uniforms and cleaning during the day
  • Consider markers for specific areas to indicate they are “clean”
  • Develop logs for recording sanitization times
  • Consider using scanning tools such as FotoFinish to automatically time and date stamp when an area has been cleaned
  • For added transparency, audit cleaning frequency and quality
  • Contact your service provider about quality control applications or contact an outside service provider to conduct validation tests.

PPE Use, care and maintenance

There are different PPE (Personal Protective Equipment) requirements for each stage of response. In pandemic situations, the availability of PPE may become scarce. Care for your PPE so that you don’t have to utilize more than what is needed for the job. Always determine which PPE is right for the situation by following the operational guidelines

Sequence of Steps

Wearing the N95 Masks

Six steps to wearing the №95 mask

PPE Removal

The order of removal of PPE reduces the risk of contamination. The importance of hand washing is also critical for PPE removal. DO NOT reach to face or eyes with gloved hands. You may be tempted to do this after wearing a mask for such a long period.

Gloves are the most contaminated item for your operations because they have contacted many surfaces.

Although low risk, clothing used for clean-up operation may have contacted surfaces

  • Do not shake clothing after removing from your body
  • If possible, launder clothing or place in separate bag for laundering later
  • Shower with soap and water before interacting with family members as a general best practice
  • PPE material such as safety glasses and some respirators are intended for multiple uses
  • Wash safety glasses with soap and water. Dry with clean paper towel and store in a non-contaminated zip lock bag.
  • Disconnect and store respirator filters, if used, within zip lock bags to prevent them from becoming contaminated

Proper removal of gloves

Operational Response

Stage 1

Stage 1 involves cleaning and sanitizing in one step

  • If the surface is dirty, refold cloth and wet wipe again after cleaning to ensure proper application of disinfectant
  • Always ensure that the cloth is “wet wiping” the surface to ensure that disinfectant contacts surface properly. Re-soak as necessary to ensure proper coverage.
  • For electronics that are sensitive to moisture, ensure that the rag is moist and not dripping with chemical solution
  • No need to manually dry instead, allow surfaces to air dry

Stage 2

The main difference with a stage 2 response is that the surfaces undergo a two-step disinfection process

  • Stage 2 responses typically apply when there is indirect exposure at the worksite e.g. a co-worker has a symptomatic family member and attended the worksite
  • Stage 2 responses are for small spaces. If the space is large, or if there is a confirmed case, a stage 3 response is preferable.
  • When disinfecting, regardless of the research for the type of virus/pathogen, apply the chemicals to remain wet for the contact time required for the chemical.
  • This means that after the one step clean + sanitizing, apply the disinfectant again onto non-porous surfaces generously so that it can remain wet for a longer period
  • Continue to other areas while the treated area remains wet
  • It may be necessary to return to areas to remove excess moisture, or allow to air dry if there is no urgency to reopen the facility

Stage 3

  1. Supervisor screens for symptomatic staff and excludes them from cleaning operations
  2. Orientation meeting should be included– the order of operations may change after understanding the site layout
  3. Supervisor does a Pre-walk Evaluation (in full PPE gear).
    Patrol affected zone to assign and plan work function.
    Supervisor will identify cleanable areas and omit/isolate sensitive equipment
    that cannot be subject to moisture
  4. Sequential sanitizing of touch points and known/affected areas happens after.
    Start from the least contaminated to most contaminated (alternatively use separate material).
    Surfaces will be damp wiped with disinfectant and force will be used to apply friction and remove dust, debris, soiling, biofilms etc.
    Where practical, items will be moved and sanitized such as keyboards, mice, phones etc.
    Cannot sanitize paper, or sensitive items, if possible, remove/move them.
  5. Secondary treatment with disinfectant.
    Depending on the size of the “affected zone” an electrostatic sprayer or alternative method will be used to coat the surface with disinfectant solution.
    Application and effectiveness will be subject to “contact time”/“Dwell Time”.
    Markers help with efficiency but sometimes will not adhere to a wet surface so you can apply to floor.

The main difference with a stage 3 response is the secondary application of chemical with specialized equipment and PPE revisions. Stage 3 responses typically apply when there is a confirmed case. When we don’t know what that person was in contact with or where droplets landed we target as many accessible areas as possible.

Post Decontamination – Basic Process

At the end of your operations there are considerations that all you should be aware of:

  • Quality Considerations – You need to verify that the job has been completed as per scope to avoid having to suit up again with PPE and redo missed areas
  • PPE Removal – The steps in removing PPE must follow a sequence to avoid potentially contaminating or infecting yourself
  • Personal Hygiene – Lastly, even with the best precautions, hand hygiene and personal hygiene is a necessary step

What is Clean for Health?

The world has changed and GDI believes that now is the time to begin implementing enhanced cleaning protocols. We aim to not just visibly clean, but to clean for health.

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