Spring and summer rains can create additional challenges when it comes to building a trench and maintaining trench safety. Knowing how to handle the extra moisture is critical to ensuring the safety of your workers and preventing a cave-in.

Keep these tips in mind.

Make sure to classify the soil type correctly

A competent person must classify soil as Type A, B or C, C being the weakest. Moisture in the soil will affect its strength and possibly its classification. “Err on the side of caution by downgrading if you're unsure," advised Eric Partenheimer of United Rentals' Trench Safety division. The soil classification will help guide you to the right protective system. “If there is a lot of moisture, it could be a shield/slide rail system or sloping. If the soil is more stable and it meets the benching criteria, benching is an option along with shoring,” said Partenheimer.

Stay on top of changes due to rain

Water can make the sides of a trench less stable. A competent person must inspect the trench at the start of each shift and whenever conditions change, including after a rainstorm.

Know the rules about standing water

According to OSHA, workers must stay out of excavations that contain accumulated water — as well as those in which water is accumulating — unless adequate precautions have been taken. Those precautions might include special support or shield systems to prevent a cave-in, water removal or the use of a safety harness and lifeline.

Remember that busy season is no excuse for shortcuts

Trench fatalities are on the rise, but they don’t need to be. According to OSHA, most fatalities occurred when no protective system was used. Workers shouldn’t pay the ultimate price in the name of productivity. They should never enter an unprotected trench or excavation deeper than 5 feet. If you’re unsure what system to use to secure a trench, a United Rentals Trench Safety representative can guide you to the proper solution.

Marianne Wait is an editor and writer who creates content for Fortune 500 brands.