We did MOPP4 training in Ft. Jackson, SC in AUG. We were supposed to wear full MOPP4 for 3 hours, and OPFOR was VERY generous in their employment of CS gas to simulate a gas attack. After about 30 minutes, I took off my M17a1 Mask and told my foxhole-buddy, "I'd rather die in a gas attack" than stay in MOPP4.
Absolute misery.
We had heat casualties and dehydration by guys sitting still in their foxholes. I can't imagine being in West Africa moving bodies, buckets of puke/blood/bodily waste, bringing food back and forth, etc.
In South Korea we were forced to stay in MOPP4 for 12-14 hours in August. They threatened LORs and Art 15 for anyone caught taking their gear off. As I recall 24 people ended up in the hospital.
They even wanted the depot maintenance guys who had been scheduled for 2 years to climb the 400 foot tall radio tower in MOPP4. Those guys packed up and said we’ll be back in 2 years.