If parts of your job require personal protective equipment, chances are you’ve been told that it won’t keep you safe if you don’t wear it.

Which is true, as far as it goes.

But depending on the types of hazards you’re exposed to, even steps as basic as the order in which you put on and take off different types of PPE can make a critical difference in avoiding injury or illness, as the U.S. Occupational Safety and Health Administration acknowledges in its rule requiring businesses to provide training in donning and doffing safety gear.

Read More: Safety Pro Talks PPE in Manufacturing

While the steps and the correct order vary by both equipment and situation, safety experts agree that extra care is required when removing safety gear, since the likelihood of it being contaminated is significantly higher.

While donning is typically less risky from a contamination standpoint, the order in which workers put on PPE determines how different pieces are layered and can help or hinder safe removal.

“Employees working with chemicals, hazardous materials, biological materials, and animals” or in “medical and potentially infectious environments need to handle PPE properly when removing it from the body to avoid contaminating themselves and surfaces nearby,” the University of Washington’s Environmental Health and Safety office warns in written guidelines for employees in units from machine shops to labs.

Watch: Ansell Suits Type 3/4: Donning and Doffing

Disposable items, such as gloves, sleeves, shoe coverings and aprons should be peeled off and turned inside out in the process so that any contaminants aren’t exposed, the office says. Reusable items should be rinsed off first, then peeled off so that the contaminated surface is inside.

Guidelines for donning and doffing PPE correctly are widely available in videos and brochures from the U.S. Centers for Disease Control and Prevention, intended to help users avoid contamination or infection. They include:

Manufacturers of safety gear have also published donning and doffing procedures tailored to their equipment.

Watch: How to don a Tyvek coverall

In a video on DuPont's Tyvek coveralls, the company suggests starting with protective feet coverings, then—while sitting down—removing the coverall from its packaging and pulling it over existing clothing to about the waist level. Next, workers should put on an inner layer of gloves, pull the coverall over their shoulders and secure it, DuPont says. Afterward, put on an outer layer of gloves.

Watch: How to remove a contaminated coverall

Doffing, for which DuPont suggests an assistant, basically reverses the earlier procedure. The assistant breaks any seals on the coverall, then peels it back, starting from the head, while ensuring that the outside of the coverall only touches other portions of the exterior, keeping any contaminant covered. Outer gloves are removed with the coverall. Next, the assistant helps remove the feet coverings and goggles, if worn. After that, the worker—still wearing the inner pair of gloves—can remove a respirator, if worn, and peel off the inner gloves inside out.

For additional PPE Safety Tips, check out MSC's Safety Guide Book.