Think of the required physical aspects of the task. What will make the environment accessible, keep the student safe and allow them to be an active participant? What lab equipment must be manipulated?
Think of room temperature, noise, fumes, dust, odors, and allergies. Also consider the ability to speak and/or communicate, and the visual aspects of the task or assignment.
Is the assignment done with a group, partner or individually? What memory and communication skills are needed? What is the level of complexity of the task.