Clearance With One Bad Number and One Bad Pump

Clearance is not achieved, and the correct action is re-clean and re-sample - not to discard the inconvenient number.

• The criterion. Clearance is judged against the 0.01 f/cc PCM criterion, and the failure of a single sample prevents a passing determination. At 0.012 this sample is above it.
• The calibration invalidates the sample. A pre/post flow difference of roughly 6% exceeds the plus-or-minus 5% validity criterion for a personal or fixed-location sample. That means the sample volume - and therefore the calculated concentration - cannot be trusted.
• The trap is treating an invalid sample as a pass. You cannot keep the number when it helps and call it invalid when it does not. An invalid sample is no data. With one of five samples unusable, you do not have a complete clearance data set, and you cannot certify clearance on four samples plus an unknown.
• Do not subtract the outdoor value to rescue it. The clearance criterion is applied to the inside samples; subtracting the outdoor average is not a general license to convert a failing result into a passing one, and it certainly cannot fix a bad pump.
• What to do. Clean again, verify the enclosure and the decontamination unit are dry and functioning, re-sample with pumps calibrated and post-checked within tolerance, and hold the space until the new set passes. Re-calibrate or retire that pump before its next use, and log it.

Both are defensible or indefensible depending on sequence and condition, and the monitor needs to establish which one this was.

• HEPA shutdown during sampling. Running aggressive sampling with the air machines off is a recognized way to sample the air the occupants will actually breathe rather than air that has just passed through a filter. It is a defensible choice if final cleaning was complete before the machines were shut down, and if the shutdown is documented in the SOP and the log. It becomes a problem if the machines were off while cleaning was still going on, or if the shutdown was improvised.
• Shower use 30 minutes before sampling. A shower generates moisture and air movement. Sampling in a damp enclosure, with water on surfaces and humid air, is not the same measurement as sampling a dry, finally cleaned space, and high humidity can affect cassette loading and analysis. The right sequence is: complete cleaning, dry the space, then sample.
• The practical question for the monitor. Was the enclosure clean and dry when the cassettes went in? If the answer is uncertain, that uncertainty compounds the calibration problem - you now have two reasons the data set cannot support a clearance certification.
• What the monitor should do. Do not sign the clearance. Write the sequence of events into the log with times, note the pump failure, document the condition of the space at sampling, and direct the re-clean and re-sample. The occupied-Monday request is a scheduling problem; a signed clearance you cannot defend is a liability problem.

Hold the load until the containers are correct.

1. The unlabeled bag cannot ship. Each container must be labeled with the generator's name and address and identify the contents as asbestos waste, so that anyone who handles it downstream - hauler, landfill operator, emergency responder - knows what it is. An unlabeled bag is a DOT and waste-handling violation and it breaks the chain that the manifest is supposed to create. Open it, re-label it, re-seal it with a fresh bag if the seal was compromised.
2. Double 6-mil is acceptable, but verify the seal and the fill. Bags should be goosenecked and taped, not folded and stapled, and not overfilled so that the outer bag bursts under handling. Check for punctures.
3. The waste shipment record/manifest must be complete and accurate - generator, transporter, designated disposal facility, quantity, and type - and the facility must be one authorized to accept asbestos waste. The manifest follows the load; it does not get filled in at the gate.
4. Check the outer packaging against shipping requirements. Friable asbestos waste is regulated in transportation and may require marking beyond the asbestos label, depending on the quantity in the package and the applicable hazard thresholds. Verify the current requirement rather than assuming the 6-mil bags are the whole story.
5. Sharps and heavy debris go in rigid containers, not bags.
6. The occupied-Monday pressure is not a reason to load a non-compliant truck. A rejected load at the landfill, or a hauler who refuses it, costs more than the delay.