What makes Excelta 213N series brushes Cleanroom safe?

Two things. First, Excelta 213N brushes are made with a static dissipative acetal called Statigo9. This Statigo9 material is as durable as nylon, thick enough to perform mechanical work, and does not shed or slough. Second, The bristles are mechanically clamped into the handle for maximum fiber retention without the use of adhesives that could contaminate the work area.