Proper containment minimizes spreading of contaminants
As part of a mould abatement project, erecting proper containment is important to prevent spreading contaminants to other parts of the structure. There are 3 different types of containment we might use, depending upon conditions:
- Source Containment
- Local Containment
- Full-Scale Containment
Source Containment might be appropriate if there is a very small amount of mould, say less than 10 square feet. We would use 6 mil poly sheeting to directly cover contaminated surfaces, such as walls, minimizing disruption to the spores. We would use 6 mil poly bags to enclose contaminated contents. The objective is to secure and remove the contaminated objects from the structure so that they can be cleaned or disposed-of.
Local Containment is more complex and is used when larger amounts of mould are observed or suspected, say a surface area up to 100 square feet. Again, we use 6 mil poly sheeting, preferably with a flame retardant rating. Temporary walls are erected using the poly sheeting, typically with spring loaded poles, or even stud walls. The poly sheeting is secured to the walls with tape and spray adhesives, or even staples if attaching to unfinished wood. Once the containment barrier has been erected, the contained area is put under negative pressure using a negative air machine, which sucks air out of the contained area. The negative air machine is equipped with a High Efficiency Particulate Air filter (HEPA) to capture airborne particles.
Full-Scale Containment is used when an area >100 square feet is affected, or if an entire room or section of a building is contaminated. The methodologies are essentially the same as with Local Containment, however the scale is different. With Full-Scale Containment, there is also the consideration of filtering make-up air to the contained area.