Environmental Sensor Data

data wrangling for various environmental sensors

instalation and use

• clone from github
• install dependencies with npm ci --omit=dev
• assign the value of your Mapbox access token to the MAPBOX_TOKEN environment variable
• start the server with npm start
• navigate a web browser to the url displayed at startup
• drag or pick data files to import

Environment

variable	description	default
MAPBOX_TOKEN	Mapbox access token	none
HTTP_HOST	network interface to bind to	localhost
HTTP_PORT	TCP port to listen on	0 (auto)
DB_PATH	location for SQLite database file	./measurements.db

Package Dependencies

• @robireton/chrono
• adm-zip
• better-sqlite3
• express
• express-fileupload
• express-handlebars
• serve-favicon
• uuid

General Notes

• coordinates for measurements are interpolated (linear) from position data
• coordinates values are retained with enough precision to locate measurement within a few meters
• measurements are rounded to the nearest integer
• might work on Windows, but hasn’t been tested

Plume Labs · Flow

How do I export my Flow data?

Note: You must have updated your Flow App to at least version V1.2.0 (iOS) / V1.3.00 (Android)

You can export your entire data history right from the application! Follow these steps to have your Flow data sent right to your account email address. You'll receive a zip file containing a set of .csv files with your pollution measures, and a set with your GPS data. Every measure is timestamped and is expressed in Plume AQI and in ppb or µg/m³.

timestamp	date	NO2 (ppb)	VOC (ppb)	pm 10 (ug/m3)	pm25 (ug/m3)	NO2 (Plume AQI)	VOC (Plume AQI)	pm 10 (Plume AQI)	pm 25 (Plume AQI)
1540905674	2020-01-01 00:00:00	15.292587280273	4946	14	7	14	147	14	14

Please remember that your Flow data may contain GPS information so be careful about how you share it!

Data Ingest Notes

• measurements consisting of missing particulate matter values and zero NO₂ and VOC values are discarded
• only a single set of measurements for a given time and place are stored
• NO₂ and VOC measurements stored with units ppb (parts per billion)
• pm10, pm2.5 & pm1 measurements stored with units μg/m³ (micrograms per cubic meter)

HabitatMap · Airbeam

• Important data files swap latitude and longitude values! We correct on import.
• data for different sensors are concatenated vertically in one CSV file

unspecified X-ray fluorescent (XRF) soil analyzer

• measurements are stored per element, except LE which is the total of all light elements
• null measurements are skipped
• dates and times are assumed to be local time
• lines of data are very wide and look like:

Instrument Serial Num	Reading #	Date	Time	Method Name	User Factor Name	Test Label	Collimation Status	Latitude	Longitude	Units
803682	15	2021-05-05	13:19:29	Geochem(2)		15	No	39.251356377	-84.451680306	PPM

Each line also has a series of columns for each element that look like:

Mg Compound	Mg Compound Level	Mg Compound Error	Mg Concentration	Mg Error1s
			2070	101

The last column is info

Perspective