A boiler suit is a one-piece garment with full-length sleeves and legs like a jumpsuit, but usually less tight-fitting. A one-piece suit avoids the potential problem of loosened soot entering the lower half of one's clothing through the gap in the middle. As the fire hole opening is only just large enough for a fit individual to negotiate, a one-piece suit also avoids the problem of the waistband snagging on the fire hole as one bends to wriggle through, or of jacket tails snagging if one has to come out backwards.

A boiler suit is a one-piece garment with full-length sleeves and legs like a jumpsuit, but usually less tight-fitting. A one-piece suit avoids the potential problem of loosened soot entering the lower half of one's clothing through the gap in the middle. As the fire hole opening is only just large enough for a fit individual to negotiate, a one-piece suit also avoids the problem of the waistband snagging on the fire hole as one bends to wriggle through, or of jacket tails snagging if one has to come out backwards.