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A consumer's guide to disinfecting after COVID-19

Many companies that lack the proper training and understanding of the disinfection process are offering services they are ill-equipped to provide.

By Jeffrey Gross

Cleaning an environment where someone has tested positive for COVID-19 requires using appropriate methods and personal protection equipment for anyone working in the area. (Photo by Getty Images)

With the potential reopening of businesses and offices, it is predicted that there will be a rush for cleaning and disinfecting services. Understanding what type of services a business requires before reopening and then finding the proper company to provide them is vital.

Since the spread of the COVID-19 virus began, it seems like everyone from maintenance companies to carpet cleaners to painters and exterminators is offering disinfecting services. The issue is that many of them do not have any infection control training or understand the requirements for proper disinfection. Here are some factors to consider when determining a company’s qualifications.

Find out if the company has any experience performing disinfecting services before COVID-19. Training for disinfection does exist. OSHA Hazwoper covers Infection Control and Hazard Communication. Infection Control Risk Assessment (ICRA) courses exist that are designed for construction/maintenance staff that work in medical facilities. Additionally, treating a location with a confirmed case vs. what is being called “proactive disinfecting” requires a different level of training and experience. This training is essential for learning how to apply a disinfectant product and how not to get sick while doing it, how not to get others sick and how not to spread the virus if you are unaware you have it.

PPE 101

There are a few different levels of protection and several other reasons for wearing Personal Protective Equipment (PPE). Anyone not wearing any PPE to apply a disinfectant is violating OSHA standards that require gloves and respiratory protection when handling or applying chemicals. Beyond that, the biggest reason for people handling the disinfecting to wear PPE is to prevent asymptomatic workers from spreading the virus. The only way to prevent someone from spreading the virus unknowingly is to have them in full PPE when they enter and work in a facility. The standard level of PPE is as follows: hooded coveralls, goggles, gloves and a respirator (can be a half-face respirator or N95 mask, cannot be a surgical mask).

When there is a confirmed case in a space within the past 14 days, the risk is much higher. Anyone entering the space to work should be fully HAZMAT/biohazard trained and be donning a higher level of PPE. Very few workers have this training, and they are trauma cleanup workers who would handle a death scene or an anthrax exposure. These workers wear Powered Air Purifying Respirators (PAPR), which are a full hood with an air pump. It is not just a higher level of PPE that distinguishes them; it is the training on how to don and doff the PPE without cross-contamination, that is the hard part.

Disinfection basics

Disinfecting involves the application of a chemical that is meant to kill or deactivate any contaminant on a surface, be it a virus, bacteria, fungus, or any inorganic substance that may make people sick. Many chemicals can claim to perform these functions, and the EPA has published a list of the acceptable chemicals for this purpose. When a company offers disinfecting services, they should identify what product they are proposing to use and why. They should also provide a Safety Data Sheet (SDS, formerly MSDS) from the manufacturer. OSHA requires they have this with them when they are working, but it’s better if the company provides it with their proposal.

What types of products are out there? Too many to list, but I will discuss the most common chemical compounds used. Two on the EPA’s list are quaternary ammonium compounds and hydrogen peroxide-based chemicals. The quaternary ammonium compounds are what most household disinfectant products and many commercial restoration or janitorial products contain. They are effective and cost-effective, but leave a residue behind that does need to be cleaned.

Peroxide-based chemicals are an alternative for areas where residues may be an issue (i.e., supermarkets, pharmacies, pet food places, daycare centers). There are several types of peroxide-based products; some are proprietary. If cost were no factor, the peroxide-based would be used more often; however, since the quaternary compounds are both effective and cost-effective, they are used more often.

Delivery methods

Many companies advertise disinfecting without explaining the process or how they will apply the products. No company should say they are “disinfecting” as that is an incorrect description. It is not enough to explain how they plan to “apply a disinfectant” without disclosing the process or service being purchased. The following are the most common methods of delivery, and the right process usually involves a combination as opposed to any one application by itself.

Ultra-Low Volume (ULV) Fogging – This method covers a wide area with minimal product but does not give the best coverage on surfaces or enough dwell time of the chemical to be effective. The biohazard teams use this as a first step to get any particulate that may be floating in the air to settle, and that’s where its effectiveness ends. The virus is also more likely to be transmitted from touching a surface than from an airborne particle (unless someone infected is coughing or sneezing right in front of you).

Electrostatic spraying – This method electrically charges the molecules of the chemical, making them attract like a magnet to surfaces. It does give better surface coverage than ULV fogging or wiping a surface by hand, but in my opinion, it is not enough on its own.

Hand to surface wiping – As the old saying goes, nothing beats good old-fashioned elbow grease. This should be part of any protocol. But again, if the workers are experienced, they will know the few rules that need to be followed. It is not damp wiping, it must be wet wiping, you have to leave enough disinfectant on the surface to stay wet for the recommended dwell time and also the cloths should be changed often and never reused, or you can end up spreading the virus around using this method.

Airless sprayers – These emit a high volume on surfaces, which is good for dwell time but is not appropriate in all types of locations. This is good for disinfecting a stadium where there is a high volume of durable surfaces. You would not use this in an office environment with papers and electrical/computer components.

Putting into practice

A responsible company will provide its proposed process and explain why they have chosen it. Here is just one example to consider.

Standard Operating Procedure (SOP) – An SOP to treat an office space as a proactive additional measure before re-occupancy looks something like this; ULV fogging and then hand to surface wet-wiping in offices and cubicle areas, electrostatic spray followed by hand to surface wet-wiping in traffic areas, lunchrooms, bathrooms and other congregating spaces. Hand to surface wet-wiping is not of every square inch of the area but rather of high-touch surfaces like doorknobs, light switches, elevator buttons, desktops, keyboards, phones, cabinet doors, tops of low walls, and walls in traffic areas (knee to shoulder height).

Dwell times – Dwell times refer to how long the chemical should stay wet on a surface for it to effectively kill or neutralize any contaminants. The average dwell time for most quaternary compounds is 10 minutes. This means the surface has to be wet for 10 minutes for it to be effective, not something you will accomplish with a damp wipe or ULV fogging alone.

Surface prep – This is where it gets tricky and is why the mechanical delivery methods alone are not enough. If there is dirt/dust/debris/residue on the surface, then you cannot effectively disinfect it. That is where the wiping of the surface comes in; it makes sure that you remove the residue and, at the same time, leave a coating of the chemical that will dwell on the surface. Unfortunately, this does mean that some residue will remain that will have to be cleaned up later, but better that than ineffective disinfecting.

Beware of snake oil salesmen

Here are some products or processes designed to make money for someone with little or no benefit.

HVAC/duct cleaning – HVAC systems are the least likely affected by the virus. Even if some virus was sucked into the system, it would have likely been captured by filtration or settled within the system rather than being blown back out and still be viable enough to infect someone (this applies to a building, not an airplane). Now there may be other reasons to address the HVAC system if it has been inactive for two to three months but not due to the virus itself.

HEPA air filtration – There are some less reputable companies in the environmental or restoration industry using these while doing COVID-19 disinfections and saying they will help capture any airborne virus. Based on available information, we know that unless someone is standing there coughing or sneezing in front of you, you are unlikely to find the virus in the air. If the airborne virus was a concern, the ULV fog can knock that out of the air at a fraction of the cost.

Ozone generators – These are very effective for odor removal and could kill the virus with enough dwell time, but ozone is also a gas and oxidizer that is harmful to breathe and can fade some surfaces. It would have to be used in an unoccupied space and then be aired out before occupancy.

Carpet treatments – Companies are proposing to spray a disinfectant on carpeting in public areas. This is ridiculous because of all surfaces, the virus does not last more than a couple of hours on carpets, and people are not likely to touch the carpeting.

When it comes to pricing, many companies are pricing this work by the square foot but are not clear about what is being purchased. That means don’t just ask what process or method they propose to use but also how many people they will send, how long it will take, how much equipment they will bring and how many chemicals they are proposing to use.

Finally, the most important thing to know is that hiring an outside company to do a one-time process is not the end-all for this situation. A vigilant protocol of daily disinfectant wipe downs of touch-prone surfaces is the most effective process to limit the spread of the virus.


Original article shared here:

Waterford, Troy, Farmington Hills, Southfield, Rochester Hills, W Bloomfield, Pontiac, Royal Oak, Novi, Commerce, Orion, Independence, White Lake, Madison Heights, Oak Park, Auburn Hills, Oxford, Birmingham, Ferndale, Highland, Oakland, Michigan,COVID-19

The Huttenlocher Group

1007 W Huron St, Waterford , MI  48328

(248) 681-2100

1007 W Huron St, Waterford Twp, MI 48328

(248) 681-2100

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