Working the smeared-tube case end to end

Return to the tube from the opening problem: a leak-resistant transport bag with a torn seam, and a primary tube whose exterior is visibly smeared with blood. Work through the case to see the control bundle applied in the order it is actually used at the bench, not as a checklist recited after the fact.

The bench tech puts on gloves before opening the specimen bag at all, because hand contact with blood on the primary tube is reasonably anticipated the moment the bag is visibly compromised. Opening a torn bag bare-handed would be a work-practice failure regardless of what PPE is available later. On inspection, the tube exterior is contaminated, so the standard's own containment rule applies: a contaminated primary container goes into a secondary container that prevents leakage before any further handling or centrifugation. This is an engineering and work-practice step, not a PPE step; the tube is contained before it is spun.

The tech loads the now-contained tube into a centrifuge fitted with a sealed rotor safety cup, an engineering control consistent with CLSI M29-A4's emphasis on containment for centrifugation, rather than trusting gloves alone to stop an aerosol generated by a cracked tube mid-spin. After centrifugation, uncapping the tube carries a reasonably anticipated splash risk, so the tech was already wearing a mask with goggles before starting the task, satisfying the eye/face protection requirement. A small droplet spatters toward the tech's face during uncapping; because the eye protection was already in place, no exposure to a mucous membrane occurs. This is what a control bundle working as designed looks like: nothing dramatic happens, because the containment and PPE were staged before the risk arrived, not improvised after it.

After aliquoting is complete, the tech removes gloves and performs hand hygiene immediately, the trigger the standard requires after glove removal. Hands are not visibly soiled, so an alcohol-based hand rub is the appropriate choice under CDC's 2002 guideline; if blood had reached bare skin, soap and water would be the right call instead. The contaminated disposable pipette tip goes directly into the sharps and biohazard container at the bench. The tech does not attempt to recap or manipulate any sharp by hand at any point in the sequence.

No exposure incident occurred in this case. That is the point of the example: it demonstrates prevention through a correctly sequenced control bundle, not a response to a failure. The bundle, secondary containment, a sealed centrifuge cup, mask and goggles, gloves, and immediate hand hygiene, reflects the hierarchy of controls applied in order, with PPE closing the last gap rather than substituting for the containment engineering that came before it. Contain a contaminated container before you spin it, and have your eye protection on before you uncap it, not after a droplet reminds you.