Electrostatic Disinfecting Sprayers: Frequently Asked Questions
As one of the newest (and safest, when using the EvaClean System or EMist sprayers) disinfection techniques, electrostatic disinfection is very much a hot topic in the cleaning world, across all industries as well as among the general public. We receive quite a few questions from our customers, so we’ve put together this primer on all things electrostatic disinfecting. As a note, we offer the EvaClean infection prevention system, featuring Protexus Electrostatic Sprayers used with PURTABS disinfecting and sanitizing tablets that dissolve in water to create the disinfectant solution, and the answers to some of the questions below directly relate to Protexus and PURTABS.
About Electrostatic Disinfecting
What is an electrostatic sprayer?
Electrostatic sprayers are the newest tools in the cleaning industry, used to disinfect surfaces with electrically charged particles for even, complete disinfecting coverage. To the untrained eye, these just look like “spray guns” but in fact, they're advanced disinfection technology based on innovations going back more than 50 years. They’re also available as backpack sprayers for more square foot coverage.
What is electrostatic disinfecting?
Electrostatic disinfection is a process whereby surfaces are disinfected with electrically charged particles for even, complete disinfecting coverage. This is done by using an electrostatic applicator that gives a negative charge to the disinfecting solution as it exits the nozzle.
Electrostatic sprayers charge disinfectants as they pass through a sprayer nozzle. This generates charged droplets that repel one another and actively seek out neutral surfaces, which they stick to and even wrap around to coat all sides. The result is a uniform coating of disinfectant on sprayed objects, including hard-to-reach areas that manual disinfectants can miss. The technology also helps avoid liquid pooling often associated with trigger sprayers.
How does electrostatic disinfection work?
While it may sound complicated, the technology is simple to understand. Electrostatic sprayers use positive and negative charges to make disinfecting solutions electromagnetically stick to targeted surfaces. No matter which angle you disinfect a surface from, the charge created by the electrostatic sprayer makes the disinfectant wrap around and cling to the entire surface.
How long does electrostatic disinfection last?
Electrostatic disinfection lasts until the surface is touched again. It’s important to note that electrostatic cleaning does not create a protective barrier. It leaves surfaces disinfected until they are next disturbed. For example, if you disinfect a hand railing with an electrostatic sprayer, it will kill any pathogens on the surface until it is next touched, when it will need to be disinfected again.
Why should I choose electrostatic disinfection over other methods?• It's totally touchfree - just point and spray for complete disinfection!
• The application is efficient and controlled, helping avoid overspraying or overuse of disinfectants.
• You'll save time - on average there's an 80% time savings over traditional disinfecting methods.
• It covers up to 3x more surfaces than using sprays/wipes and other disinfecting methods with 360° disinfecting & sanitizing of those surfaces.
• When used at a 1076PPM (parts per million) dilution, the system is effective at killing the virus that causes COVID-19.
Techniques and Recommendations
Does the person spraying have to have any specialized PPE?
While no specialized personal protective equipment (such as a respirator or disposable coveralls) are required, it’s best practice to use gloves when handling PURTABS, and wear a mask while using the Protexus electrostatic sprayer at high PPM concentrations.
Must the room be entirely void of people?
It's recommended to have the room empty so you don’t spray on or near anyone, and to achieve full disinfection of surfaces. It is safe if there is no alternative (for example, there are two people working on cleaning and disinfecting the room). Just be sure to maintain distance from the other person while you’re spraying.
EarthSafe, the parent company of EvaClean, manufacturer of Protexus electrostatic sprayers and PURTABS disinfecting tabs, conducted independent third party testing (personal air sampling) with American Environmental Consultants, Inc. These were performed by a trained industrial hygienist using OSHA and NIOSH sampling techniques. All results verified that spraying PURTABS with the Protexus Electrostatic Sprayer fall below published accepted Permissible Exposure Limits and Threshold Limit Value. There are no OSHA or NIOSH exposure concerns for workers or when using the sprayer in a public setting.
If not, and it's a 12,000sq ft room with a 50" ceiling, how far away from the sprayed area must they stay and for how long?
Again, as stated above, it’s recommended that the room be clear while spraying. To achieve complete disinfection of the area once sprayed, follow the appropriate dwell times (the time the surface must remain wet in order to kill viruses - in this case, 10 minutes if you’re spraying at 4306PPM or parts per million dilution of PURTABS in tap water). The ceiling height in a room will not affect the disinfection of the room.
How long before people are allowed to use the sprayed equipment?
The sprayed equipment can be used after the appropriate dwell time (see above) has been achieved. At that point, the surface will be dry, and disinfected. Remember that electrostatic cleaning does not create a protective barrier. It leaves surfaces disinfected until they are next disturbed. For example, if you disinfect a hand railing with an electrostatic sprayer, it will kill any pathogens on the surface after dwell time has been achieved until it is next touched, when it will need to be disinfected again.
Will the “wrap around” be effective on all surfaces and sizes?
In most all environmental conditions the electrostatic wrap allows workers to achieve 3x the coverage of a traditional spray bottle. However, in certain environmental conditions (i.e. wind, room humidity, etc.) delivery with the sprayer may not be completely uniform. Wrap should encompass 3-4 inches around each sprayed object. In certain instances, one will have to spray around certain objects and surfaces to obtain full coverage due to size, distance and substrate variations.
Can any sanitizer or disinfectant be used with the Protexus sprayer?
Only PURTABS have been tested, verified, and measured to achieve repeatable results, based on application and dwell times. EarthSafe makes no warranties or representations regarding products that are not part of the EvaClean System.
Can this be used in offices?
Yes, the Protexus sprayer is suitable for offices, as well as in educational facilities, fitness facilities, homes and hospitality settings as well as for healthcare.
Does it leave a damp residue on fabrics or paper?
Yes, electrostatic spraying will leave a residue on papers. Any important papers in the area being disinfected should be removed, and those left behind, not directly sprayed on.
Are there concerns about using it around computers, phones or other electrical devices?
None at all. EvaClean's Protexus Sprayer, combined with PUR:TABS, can be used around standard office equipment such as laptops, desktops, keyboards and monitors but should not be applied directly to any sensitive electronics. Before applying, reference the equipment manufacturer's instructions for cleaning and disinfecting.
For kitchen surfaces and eating surfaces is there any precautions or cleaning needed after Protexus/PURTAB application?
At the 1076PPM concentration (the PPM concentration that's food safe), you would want to rinse any areas that come directly in contact with food; cutting boards, plates, etc. If using the 334mg tab at 100PPM, no rinse is necessary as it is NSF D2 registered.
All About Protexus and PURTABS
Does the Protexus sprayer have a safety certification?
All Protexus sprayers have ETL Certification which is the equivalent to UL and certifies that the products have met all the minimum safety standard requirements established by OSHA and carried out by Nationally Recognized Testing Laboratories. The selection of either certification largely comes down to the ETL having a larger pool of testing facilities and the ability to process registrations faster than UL. Neither carries any benefit over the other.
How many square feet will one 32 oz. tank of the Protexus sprayer cover?
A 32oz tank will cover about 800–1,000 square feet. The variation is dependent on nozzle setting and surface material.
Does the Protexus sprayer need to have EPA registration or FDA approval?
No. It is a mechanical sprayer and is simply an alternative method of application from traditional spray bottles. The electrostatic charge (which, by the way, can be turned on or off by the user) is simply an assistive mechanism to aid the user in more efficient and comprehensive application of EPA Registered chemical disinfectants and sanitizers to surfaces.
Do you still have to clean before using the Protexus sprayer?
Yes. You will still remove visible soil (unlike a one-step process where you would have to clean/disinfect every spot by keeping it wet for the required amount of time), and then spray to achieve complete and quick sanitizing or disinfection. We recommend PUR:ONE, which can be used with microfiber cloths, dry wipes, and spray bottles to clean/disinfect surfaces prior to enhanced disinfection with the Protexus Sprayer and PURTABS.
Does spraying PURTABS leave “bubble marks, or streaking” on plastic and stainless steel?
At a 4306PPM concentration, it may leave some residue, which would need to be wiped with water once dry. With all other concentrations, residue will not be left on plastic or stainless steel.
How long is the solution stable once diluted?
PURTABS are stable for 3 days once diluted and stored in a closed container. In an open container, the solution is stable for 24 hours.
Do PURTABS have a smell?
Yes. PURTABS has a slight chlorine smell that dissipates quickly after application leaving what most end users describe as a “clean” or “sterile” smell.
In residential applications what is the recommended dwell time for PURTABS to kill COVID-19 and what at concentration level to be most effective and safe for occupied households?
1076PPM is the effective concentration to kill Sars-CoV-2, the virus that causes COVID-19. The dwell time is ten minutes (the surface should be allowed to air dry), and this is the highest concentration you’d want to use in a household. A note on fabrics: you would spot test if applying near/around fabrics to ensure that it is colorfast. Non-colorfast fabrics could “bleach.”
Will this stain fabrics?
See above; PURTABS should not be used on non-colorfast fabrics, wool or silk fabrics, or any fabric with a special finish. If applying around fabrics, test on an inconspicuous area prior to use.
What are PURTABS made of? What chemicals are in it?
The PURTABS Chemistry is based around NaDCC, an organic chlorine donor which yields Hypochlorous Acid (HOCl) and Monosodium Cyanurate (NaOCl) when dissolved in water. This solution results in a free available chlorine count (ppm) that is easily measurable with test strips to ensure the solution concentration is consistent with usage guidelines and all of the efficacy claims and data that are on our EPA Registered Label. There are 3 tablet size options to make mixing the proper concentration simple.
For more information on electrostatic sprayers, check out the following posts:
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