ATV toxicity team report
Editor's note: The story of the ATV missions to the ISS involves not only grand happenings – lift-offs, orbitings, dockings and bitter-sweet endings – but also many small, seemingly mundane, steps carried out diligently by dedicated, passionate people. One of these involves a team of ESA experts working along side the cargo loading and fuelling engineers and technicians at Kourou – but 'behind the scenes' – to ensure that the air inside ATV meets all the required standards before docking to the ISS.
Sampling ATV-3 interior air in the S5B building, Kourou Credit: ESA/A. Novelli
Of course, when it comes to docking and delivering cargo, crew safety is paramount. And, yes, there are standards for more or less everything on board the ISS – including the atmosphere inside Station and inside ATV. After the docking, the hatch opens, and the cargo vessel becomes an integral part of Station. At that point, the two atmospheres mix freely, and there had better not be any gas or particulate matter suspended in the ATV air that could affect the crew or the Station.
Where does toxic gas come from? Think of the last time you slid into the driver's seat of a show-room car – we all know that 'new-car smell'. It's a mixture of gases that are emitted from the numerous interior fittings in a car: the leather seats, paint and coatings, the multiple types of plastic used in the dash and in the interior fittings, the carpets, etc. It's the same with each new ATV – out-gassing can cause air toxicity in the enclosed cargo volume.
Likewise, there had better not be any physical contamination on the exterior of ATV that could affect its performance – image the problems if a greasy thumbprint were to be left unknowingly on the optics of one of the laser docking telegnometers.
For a number of weeks, ESA engineers Mei Mei Stienstra and Olivier Schmeitzky, based at ESA's ESTEC technical centre in The Netherlands, have been working in Kourou to verify the air inside ATV and check the vessel overall for contamination. They've been conducting tests and checks at numerous stages – including during and after main cargo loading, after the two halves of the vessel were integrated, and after the late cargo load, which finished last week (ATV Edoardo Amaldi's hatch was closed on 16 February).
ATV-3 toxicity team at Kourou. L-R: Dimitry Tsarkov (IBMP Moscow), Olivier Schmeitzky (ESA/ESTEC), Mei Mei Stienstra (ESA/ESTEC) Credit: ESA/A. Novelli
In a telephone interview last Friday, I had a chance to ask the two about their crucial work. Mei Mei works on gases, while Olivier focuses on particulate matter both inside and on outside surfaces (including the crucial laser optics) of ATV. Here's a rough transcript of our call.