Containment and Control Operations
What the candidate must know
Containment and control aim to stop or reduce the release without increasing risk. Candidates must know the defensive vs. offensive distinction: defensive operations act from outside the hot zone (diking, damming, diverting, absorbing, plugging, patching from a safe distance), while offensive operations require entry and a higher level of training and PPE. Know containment techniques: diking, damming, diverting, retention, absorption, adsorption, and neutralization. Understand the behavior of liquids and gases, the importance of controlling ignition sources for flammables, and the limits of containment (e.g., don't contain a flammable liquid that could create a larger hazard). Know vapor suppression techniques (foam, water spray) and when they are appropriate.
Traps in questions
- Containing a flammable liquid in a way that creates a larger pool fire or vapor cloud.
- Using water on water-reactive chemicals or on liquids that float and spread.
- Forgetting that containment may require a downstream plan for disposal.
- Attempting offensive entry without the training, PPE, and backup.
Rule of thumb
If you cannot safely stop the release, contain it and protect exposures. Control the flow, not the source, when entry is unsafe.
Worked example
A leaking drum of flammable solvent: from a safe distance, upright the drum if possible, dike around the leak with compatible absorbent, eliminate ignition sources, and apply foam to suppress vapor. Do not enter the hot zone without Level B/A and backup.