The opacity limitation in many states includes an exception for how many seconds in any minute period?

The opacity limitation in many states typically allows for an exception where emissions can exceed the established opacity standards for a limited duration within a specified timeframe. This exception is often set for 30 seconds within any one-minute period.

This tolerance is important to account for short-term operational variations that may occur in normal activities, ensuring that occasional spikes in emissions do not lead to automatic violations of regulatory standards. The selected duration of 30 seconds reflects a balance between maintaining air quality standards and allowing for the realities of industrial operations. This understanding is critical for mortuary and cemetery professionals who may deal with equipment that generates emissions and need to comply with local regulations regarding air quality.