Protection against mosquitoes and ticks: Each product is tested to see how effectively it protects against Aedes mosquitoes (the aggressive mosquitoes that tend to bite during the day and can spread Zika) and Culex mosquitoes (nighttime biters that can spread West Nile). Based on our past testing, and on advice from independent experts, products that are effective against mosquitoes should be effective against other arthropods, including deer ticks.

Resists damage to materials: We test repellents on several common materials. Those scoring higher are less likely to cause damage. If you are concerned about damage, test first on an inconspicuous spot.