Use of rubber sleeves while working in a combiner box at a solar field

[Jim1952]

I am being told by my safety dept that I must wear rubber insulated sleeves while working in a combiner box or taking a LDL check on the solar field connections at the inverter after all the combiner boxes have had their breakers opened (1500VDC). They say that I have broken into the MAD distance which then requires the sleeves. I already have a CAT 4 suit on. I thought that sleeves were required only when your upper arm or shoulder could come into contact with another energized connection point or secondary voltage. Am I correct or misunderstanding the use of the sleeves?
Jim