How firm should a roll bar pad be?
Old-school roll bar padding had a reputation: hard as a rock. Modern molded padding doesn't have to be, and choosing the firmness is a real decision, not a default.
What the pad is actually doing
In contact, the pad's job is to spread and absorb energy between a human and a steel tube. Too soft, and it bottoms out, the foam compresses fully and the tube does the rest. Too hard, and it barely deforms, you've wrapped the bar in something that behaves like more bar. The useful range is in between: firm with a cushioned feel, compressing progressively through the hit.
How firmness gets specified
Firmness and density are related but distinct properties: density describes how much material occupies the volume, while firmness describes how the surface resists indentation, and standardized tests measure it directly. A shop that molds its own padding can tune both through the formulation, and verify the result with instrumented firmness testing rather than by feel, batch after batch. Published test readings for a seat or a pad are about repeatability, not marketing.
Stiffer and flexible grades exist for a reason
Roll bar pads come in stiffer grades and more flexible, heavier grades. The right one depends on the tube diameter, how the pad mounts, and what your sanctioning body requires. Fire-retardant material options exist as well, which standard applies varies by series, so the right move is to ask with your rulebook in hand rather than assume.
The practical takeaway
Don't order padding by photo. Order it by application: tube size, mounting, series rules, and where the driver's helmet actually sits. A shop that has molded a quarter of a million of these will get you to the right grade in one conversation.