| 释义 |
unhealthful day Any day in which the air quality for any of the 5 major ambient air pollutants—carbon monoxide, nitrogen dioxide, ozone, particulate matter, sulphur dioxide—exceeds an established air quality standardunhealthful day Public health Any day in which the air quality for any of the 5 ambient air pollutants–carbon monoxide, nitrogen dioxide, ozone, particulate matter, sulfur dioxide exceeds an established air quality standard. See Pollution Standards Index. Cf Unhealthy day. |