Due to COVID-19 guidelines more people are cleaning their hands with sanitizer when they get back in vehicles after essential journeys. This is good for the owner’s health, but it could be bad for the interior. Chemicals like ethanol in hand sanitizers can react with surfaces, causing them to wear prematurely unless they are protected by special finishes.

Engineers at Ford have long been tasked with testing new products on materials used in the company’s vehicles. Based on the test results the chemical constitution of protective coatings can be reformulated to ensure vehicle interiors remain looking good no matter what they encounter. Testing also applies to storage accessories, sold through Ford Customer Service Division, such as trunk liners and interior plastic covers.

“Hand sanitizer is a product we saw an increasing use of some years back so it’s been part of our testing for a long time now,” said Mark Montgomery, senior materials engineer at the Materials Technology Centre, Dunton Technical Centre, UK, for Ford of Europe. “Even the most innocuous seeming product can cause problems when they come into contact with surfaces, but things like hand sanitizers, sun lotion, and insect repellent can be particularly damaging.”

Use of hand sanitizers has boomed since the outbreak of the COVID-19 pandemic with recent forecasts suggesting that the global market for hand sanitizers will increase by almost two and a half times in 2020 compared to 2019.

While hand sanitizer helps kill germs on the user’s hands, and Ford vehicle interiors can withstand their potential damaging effects, it doesn’t mean that the rest of the vehicle is free from germs, especially if shared with other people. When cleaning, avoid using products containing bleach or hydrogen peroxide, as well as ammonia-based products as these can damage anti-glare and anti-fingerprint coatings. Household disinfectant can be an effective way to eliminate the threat.

“Particular attention should be paid to frequently touched areas such as the steering wheel, handles, gear stick, any buttons or touch screens, wiper and turn signal stalks, armrests, and seat adjusters,” said Jenny Dodman, Ford of Britain’s chief medical officer. “Seatbelts should also be high on every driver’s cleanliness check list. The seatbelt sits across you and is likely to bear the brunt of any coughs and sneezes.”

The Ford team tests material samples at temperatures that can in some cases reach 74 degrees Celsius – the temperature the inside of a car parked at the beach on a hot day might reach. In other tests they simulate extended exposure to the sun, with samples bombarded with ultraviolet light for up to 1,152 hours (48 days).

They also test plastics for strength at temperatures as low as -30 degrees Celsius when they become most brittle, repeatedly bouncing a heavy rubber ball on them to ensure the plastic doesn’t crack.