Electrostatic Spraying Techniques

Using an electrostatic airless disinfectant sprayer provides the fastest way to achieve consistent coverage of disinfectant materials on and around any grounded surface or object. Improving spraying techniques can greatly improve application speed and effectiveness to help maximise productivity on every disinfecting job.

Graco electrostatic airless disinfectant sprayers combine a high-pressure airless spray with a high-powered electrostatic charge to deliver superior material delivery and coverage for higher levels of productivity and material efficiency.

In high-pressure electrostatic airless spraying of disinfectants, the fast moving high-pressure liquid stream provides the energy necessary to generate a spray pattern. The high-pressure forces fluid through a small nozzle (spray tip) that creates the size and fan pattern width.

Along with the high-pressure spray, the electrostatic generator positively-charges the atomised disinfectant fluid to provide an even distribution and superior material “wrap” on surfaces and around complex objects. This consistent distribution of disinfectant on the surface can also help reduce the amount of material needed to achieve consistent, uniform coverage.

Without adequate grounding of the sprayer, the electrostatic charge will be minimised and result in a limited wrap on the surface being sprayed. Gloves or other PPE can limit proper grounding of the sprayer so it’s important for operators to have a solid and consistent contact with the grounding solution provided with the sprayer.

It’s important to note that many electrostatic disinfectant sprayers on the market today use a low flow or low-pressure spray delivery method. As a result, these sprayers don’t have the spraying power to the project the material far from the sprayer (often less than one metre), resulting in slower spraying speeds, requiring additional labour hours to complete the job.

The information provided below is meant to be general application guidelines. Before spraying disinfectant materials, it is critical to always refer to the chemical manufacturer’s application recommendations according to the EPC approved label.

A good spray pattern indicates that the disinfectant material is completely atomised and distributed evenly on the surface. Several techniques can help maximise the quality of the spray pattern and the uniformity of the coverage when disinfecting surfaces:

• Adjusting the Pressure
• Tip Size
• Aiming the Spray Pattern
• Triggering Technique
• Movement of the Spray Gun

Adjusting the Pressure

To achieve the best spray pattern, always start at the lowest pressure and slowly increase the pressure until you achieve the desired results. A good spray pattern will always have even, soft edges. If you have visible lines or “tails” at the top and bottom of each pattern, try increasing the pressure in small increments until the edges of the pattern soften.

Tip Size

Selecting the right spray tip will help determine the amount of disinfectant fluid sprayed and the spray pattern of the materials. Low Pressure (LP) tips are recommended when spraying disinfectants using a dedicated airless disinfectant sprayer to better control the spray and also provide the ability to reverse the tip to quickly clear out any potential clogs that may impact the spray pattern.

Aiming the Spray Pattern

Start each pass by holding the spray tip between 30-45 centimetres from the surface. Aim at the middle of each previous pass so you’ll overlap it by 50%. If you’re working with a sprayer that uses a separate hose and spray gun, hold the hose with your other hand to keep it out of the way.

Triggering Technique

The spray gun should be triggered after beginning the stroke (also called the lead stroke) and released before ending the stroke (also called the lag stroke). Start and stop the gun after each pass. The gun should move during both the trigger squeeze and trigger release. This technique prevents blotches of disinfectant materials at the beginning and end of each stroke.

Movement of the Spray Gun

To help blend each spray pass and create a fuzzy edge around the entire spray pattern, flex your wrist so the gun stays perpendicular to the surface. Fanning the gun one-way or the other will result in uneven spray patterns and possible uneven distribution of disinfectant materials on the surface. Make sure not to overreach – just reach as far as is comfortable.

In order to effectively kill pathogens that cause the transmission of infectious diseases, always make sure to completely wet the surface and ensure it remains wet to meet chemical dwell time requirements as specified by the chemical manufacturer. As mentioned earlier, always follow the chemical manufacturer’s application recommendations. 

Practice Spraying First

In order to refine spraying techniques when using a dedicated electrostatic airless disinfectant sprayer, it’s best to do some practice on a test metal object. This will provide the opportunity to fine-tune your technique and while learning how to adjust the sprayer pressure for the best spray pattern and proper atomisation of disinfectant materials.

Before you begin spraying, be sure you’ve read all safety and operational instructions that came with your airless disinfectant sprayer and have proper personal safety gear, such as eye protection and a respirator. Always be aware that airless sprayers can put out a lot of pressure – often enough to pierce skin. So, never point the gun at yourself or anyone else. Also, it’s important to make sure to adequately ventilate your work area before spraying.

Electrostatic airless spraying is the most efficient method to apply disinfectants and sanitisers. These spraying techniques will help you improve application consistency and ultimately reduce the time you need to complete disinfecting jobs.