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Purtroppo in inglese (furono presentati in un convegno internazionale).
CIAO
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GASEOUS AND PARTICULATE MEASUREMENTS ONBOARD AN ITALIAN “SAURO†CLASS III SUBMARINE ON ACTUAL DUTY.
LT L.Ricciardi, LT CDR E.Desideri (COMSUBIN )- CDR G.Ranieri (MARISTAT)- CDR A.Dollinar (MARIPERMAN) Italian Navy
M.Gallorini, G.Giaveri, E.Rizzio, L.Bergamaschi (CNR Institute of Metrology IMGC– Unit of Radiochemistry and Spectroscopy c/o University of Pavia- Italy)
Introduction
Materials and Methods
The sampling campaign was carried out onboard the Sauro Class III “Salvatore Pelosi†submarine during a crossing of the Ionian Sea in mid february (250 nautical miles), prior to NATO Exercise “Dogfish 2004â€Â.
Gas samples were drawn every 15 min by means of a Brüel & Kyaer photoacoustic spectrometer, whose probe was located in the sky of the control room, over a period of 42 hrs 15 min (sampling rate 15 min); carbon monoxide (CO) and dioxide (CO2), sulfate compounds (SOx), volatile organic compounds (VOC, referenced to propane) and water vapour were investigated. Oxygen (O2) was analysed by means of an Analox Oxymeter, together with physical environmental parameters.
Indoor air particulate matter has been analysed for the determination of trace elements and metals concentration expressed in nanogram per cubic meter. Fraction with total suspended particles as well as the respirable fraction (particles with aerodynamic diameter below 4.5 micron) have been collected onto cellulose filters by pump aspiration (Zambelli, 25 l min-1 and 3.5 l min-1 respectively). Air samplings were carried out at two permanent stations: in the control room and in the forward torpedo room; sampling times were: 6 hrs without room air purification, additional 6 hrs with air purification (Koala Sub System, D.A.TECH. Pesaro, Italy; a total of 18 stations within different compartments), and 4 hrs with the addition of KO2 carbon dioxide scrubbing system. In the latter a portable pump was available and sampling time was as follows: 3 hrs in the Propulsion Control Room respectively with and without purification (Koala); 3 hrs in Control Room. The influence of snorkel cycles, diesel engines, and standard human activities on board the submarine, were considered and recorded (i.e cooking, heads. drainage, tanks venting, etc.).
Results
Gas sampling
All gases were monitored over a period of 42 hrs 15 min, with six snorkel sessions (1 to 2.5 hrs duration). Any snorkel session would cause their concentration to drop to zero values; this was the moment when the spectrometer filter had to be changed.
CO2
Carbon dioxide concentration was encreasing after snorkel from about nil to 0.74 % (7400 ppm) whithout air purification and to 0.62 % with air purification and the same kinetics. Only KO2 would stop this trend quite suddenly and keep concentration nearly constant over a period of 7 hrs.
CO
Carbon monoxide would increase steadily from nil to 8 ppm, 7.6 ppm and 9.4 ppm after the same interventions as before, with apparently no response whatsoever to Koala System or KO2 and the same kinetics.
VOCs
The volatile organic compounds, as betraied by propane, were well affected by air filtering, causing their concentration to be stabilized at 69 % of control value without Koala (46 vs. 66 ppm); even steadier would appear their concentration when KO2 was added.
SOx
Sulphate compounds were not affected by any of the monoeuvres and their concentration always went up to 50 ppm in 6 to 9 hrs.
Particulate sampling
Total suspended air particulate and its inhalable fraction (
Results are suitably matched with those of the Himalayas air, rural and town air in Italy.