Source code for pi_weather.core.sensors.stcc4.co2_ranges

"""Definition of CO2 ranges"""

from pi_weather.utils.logs import get_logger

logger = get_logger(__name__)

# The STCC4 sensor has accuracy in this range: 400 - 5000 ppm

SENSOR_CO2_LIMIT_MIN: float = 400.0
SENSOR_CO2_LIMIT_MAX: float = 5000.0

# Air quality ranges
THRESHOLD_1: float = 400.0
THRESHOLD_2: float = 600.0
THRESHOLD_3: float = 800.0
THRESHOLD_4: float = 1000.0
THRESHOLD_5: float = 1500.0
THRESHOLD_6: float = 2000.0
THRESHOLD_7: float = 3000.0
THRESHOLD_8: float = 5000.0




def get_air_quality_index(
    co2_concentration: float | int | None = None,
) -> int:
    """
    Function to get an air quality index from the input CO2 concentration

    :param co2_concentration: CO2 concentration
    :type co2_concentration: float | int | None
    :return: Air quality index
    :rtype: int
    """
    if co2_concentration is None:
        logger.error("No CO2 concentration provided")
        return -1

    if (
        co2_concentration <= SENSOR_CO2_LIMIT_MIN
        or co2_concentration >= SENSOR_CO2_LIMIT_MAX
    ):
        logger.error("Input CO2 concentration out of sensor's range")
        return -1

    if co2_concentration < THRESHOLD_2:
        return 1  # 400-600 :=> EXCELLENT
    elif co2_concentration < THRESHOLD_3:
        return 2  # 600-800 :=> VERY GOOD
    elif co2_concentration < THRESHOLD_4:
        return 3  # 800-1000 :=> GOOD
    elif co2_concentration < THRESHOLD_5:
        return 4  # 1000-1500 :=> ACCEPTABLE
    elif co2_concentration < THRESHOLD_6:
        return 5  # 1500-2000 :=> BAD
    elif co2_concentration < THRESHOLD_7:
        return 6  # 2000-3000 :=> VERY BAD
    elif co2_concentration < THRESHOLD_8:
        return 7  # 3000-5000 :=> CRITICAL
    return -1