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Containing Construction Containments
Animation Series 3:
Containing Construction Containments
- Construction Area Contained
- Poor Containment Strategy
- Temporary Exhaust is OK
- Incorrect Ventilation Concept
Construction Area Contained
Mouse over the animated picture above to see messages which are referenced in more detail below.
Pressure relationships between rooms is designated at the bottom of each room (with a plus for positive and minus for negative pressure).
- [CONTAINMENT AREA] The room with an exhaust is being used as the containment area. A large exhaust machine (negative air machine) keeps the containment area under
SIGNIFICANT NEGATIVE PRESSURE. Blocking the supply air is helping to maintain negative pressure. The area is sealed reasonably well from all surrounding spaces (other than
the construction area). This is also helping to maintain negative pressure. Construction pollutants are flowing FROM the construction room INTO the containment area and
OUT the exhaust.
- [CONSTRUCTION AREA] The RETURN AIR in this room IS BLOCKED to insure that there is no recirculation of contaminated construction air. The construction area is
under negative pressure relative to all surrounding areas except the containment area which draws construction contaminants into the exhaust air stream. Replacement air comes
from infiltration, and from adjacent rooms above and below the construction area. An opened window in the construction room is sometimes used to improve the flow of air
into the containment area.
- [OFFICE AREA] The office area is protected against the construction contaminants because it is kept at POSITIVE PRESSURE relative to the containment room, which itself is well sealed. Additional supply air flow to this area during the construction activities can help assure positive pressure and good indoor air quality to the office occupants.