|Ask the Experts
April 27, 2022 - Updated
April 21, 2020 - Originally Posted
Hand Sanitizer Contamination
Due to the COVID-19, the plant is wanting to use a sanitizer called Sani-Cide 94 which is a quaternary ammonium sanitizer. It is going to be placed on tables with sprays and other surfaces around the plant.
Can any of the possible particles that fly to the air affect the Printed Circuit Boards?
|Expert Panel Responses
Yes. We are collecting data on many of the decontamination systems and will be publishing the soon. We have ion chromatography and sir testing.
President/Senior Technical Consultant
The short answer is yes, there is risk. The main active ingredient, dimethyl benzyl ammonium chloride, Is an ammonium salt and does contain chlorine.
Chlorine compounds, in combination with atmospheric moisture, can contribute to reduced insulation resistance and failures due to dendritic growth.
Quaternary ammonium compounds are usually made as halide salts (e.g. chloride salts). Particles that land on circuit boards will deposit these salts which are conductive and potentially corrosive. With the right conditions of quaternary ammonium salt, plus moisture, plus voltage, then electrochemical migration or corrosion could occur.
I suggest keeping the circuit boards at least 6 feet away from the spray of sanitizer, to try and avoid contact.
Not sure on this one, would need to conduct a DOE to determine. However, I have advised to use caution on using non-approved cleaners on ESD treated surfaces.
It is possible and likely to destroy the dissipative properties of the item being cleaned.
Director of Corporate Quality Assurance
Delta Group Electronics Inc.
The material warnings saying "prolonged soaking may cause damage to metal instruments" and "follow pesticide disposal instructions" would give me pause.
Metals like ENIG finishes and relatively soft solder could possibly be damaged if it will damage metal instruments. If this has to be used, assemblies, pwbs, and materials should be removed from the area until everything is dried.
PCBA Engineering Liaison
General Atomics Electromagnetic Systems Group
According to Sani-Cide 94 SDS, the material will react with oxidizers, strong acids and reactive metals. Tin, lead and copper are considered to be reactive metals but I do not believe that flying particles will affect your boards, however, direct contact will.
Keep all PCB's from coming into direct contact with the sanitizer.
Senior Manufacturing Engineer
Ten years ago, Doug Pauls and Michael Vosatka of Rockwell Collins, authored a paper for IPC APEX that provided a detailed examination of some typical hand sanitizers and hand lotions and their impact on high-reliability electronic hardware.
Their research, which included SIR (Surface Insulation Resistance), FTIR and, ion chromatography, is very timely again in today's environment. A link to the full white paper can be found at the end of the brief:
See the link that follows, it will take you to the Tech Brief. https://tinyurl.com/yafynpro
Technical Expert Sales Support
Quaternary ammonium compounds (QACs) are antimicrobial disinfectants commonly found in cleaning solutions used in residential, commercial, medical settings, restaurants and food production facilities.
While there appears to be no published guidelines for using QACs on printed circuit boards, caution should be considered since certain laboratory tests have indicated prolonged use of some types of QAC disinfectants were detected to have impaired the reproductive health of mice.
We further recommend contacting the manufacturer of Sani-Cide 94 for more details and clarification.
IMO not a good idea. The ammonium , per SE, is a urea product. Urea contains calcium. Calcium is a salt, Salts are corrosive to metallic surfaces, Therefore....IPA 90e% to 10 % DI water is a far better disinfectant for hard surfaces. CDC uses this as a guideline.
I try to keep my responses short and to point. Flowery responses provide the same results except at a slower rate. Alcohol has been a universal disinfectant for years upon years. The addition of DI water slows the evaporation rate and increases the time factor for virus destruction. Adding an ammonium factor IMO cannot help the situation, but in fact may create a problem.
Given the problems of atomizing quaternary ammonium near PCBs, a safer sanitizer containing IPA and water would be my suggestion. As a sanitizing spray, the CDC recommends spraying an IPA concentration of at least 60% . Wipes and sprays formulated with 70% IPA and 30% deionized water can be used for cleaning surfaces. The DI water slows the evaporation rate of the IPA, providing more time for cleaning. According to the CDC, IPA is effective in killing bacteria and viruses on surfaces. These chemicals will not pose the corrosion problems of quaternary ammonium sprays on PCBs.Russell Claybrook, MicroCare, LLC
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