The hydrazine incident: could both astronauts have been saved?

Question

In Europa Report, two of the astronauts (James and Andrei) are coming to the end of a space walk (and are low on air) when there's an emergency in the form of an explosion. Andrei finds a tear in his suit and is rapidly losing consciousness. James' suit is contaminated with hydrazine. He is advised to avoid re-entering the ship as doing so would contaminate its atmosphere presumably putting everybody else at risk. He therefore chooses to send his colleague back in and is stranded in space (and dies).

Now,

1. What happened to James' tether? Wasn't it Andrei who was untethered?
2. Couldn't they have used the airlock to switch suits or if there were no suits, flood it with air and rescue Andrei first? Hydrazine exposure does not appear to be (immediately) fatal.
3. Couldn't a third astronaut have helped James after Andrei had been rescued?

Considering the general attention to detail in the movie, I'm questioning the realism of this scene.

Answer 1

From wiki

Hydrazine is highly toxic, and dangerously unstable in the anhydrous form. Symptoms of acute (short-term) exposure to high levels of hydrazine may include irritation of the eyes, nose, and throat, dizziness, headache, nausea, pulmonary edema, seizures, coma in humans. Acute exposure can also damage the liver, kidneys, and central nervous system. The liquid is corrosive and may produce dermatitis from skin contact in humans and animals. Effects to the lungs, liver, spleen, and thyroid have been reported in animals chronically exposed to hydrazine via inhalation. Increased incidences of lung, nasal cavity, and liver tumors have been observed in rodents exposed to hydrazine

Hydrazine is used as propellant and fuel in aircraft and space vehicles. This might have leaked from the ship and fall on James's suit during EVA.

1. Both were tethered to the ship. When the panel blows up, James tells he still has Andrei tethered.
2. Hydrazine and humans should not be in the same breathable environment. If they used airlock to switch suits, they would have inhaled hydrazine. It seems to produce dizziness. Hydrazine would have spread throughout the ship. It seems too risky.
3. Third astronaut could have helped Andrei first. This type of unplanned EVA should have had a backup person kept ready. Here, in this scene, there is no such person.

James could have been saved if Andrei goes in first and fixes his Suit. And comebacks with a portable oxygen breather like in scubadiving, underwater breathing. James could hold on his breath for a few seconds for Andrei to fit breather to James. This link tells me that we can hold for more that one minute in vacuum. After this, they could remove James's spacesuit and enter into airlock.

Answer 2

Another possible but dangerous option would have been to rig the airlock to maintain .9ish atmosphere pressure. Assuming the ship was at 1 atmosphere, the positive pressure would keep the hydrazine out of the ship's atmosphere. James comes in, doffs the suit and then the crew opens the inner hatch pulling him out. James would have to hold his breath or be given a re-breather. The re-breather can be Left in airlock after pulling Andre out. A few things could go wrong though.

1. The airlock would have to be able vent atmosphere out to space or to a quarantined tank. If the airlock can't be rigged this way it's not possible. IE. maybe it can only depressurize into the ships tanks or cabin space.
2. It's still risky, positive pressure isn't a guarantee against ANY contamination. It depends on capable the ships lifesupport system is at handling a small amount of Hydrazine.
3. James would have to make sure he didn't contaminate his shipsuit when removing the spacesuit. He probably should fully strip naked to be honest but even then he needs to not contaminate his skin.
4. Hydrazine could contaminate the airlock walls/equipment. Meaning the crew might lose use of the airlock if not decontaminated.
5. Opening the inner hatch might not be possible against the .1 atmosphere pressure difference. Depends on the hatch orientation and if it's motor assisted and how powerful the motor is.

There's a safer option. It still has all of the above issues except #2. It assumes the following. 1.James can survive quite a while with a re-breather in a hydrazine environment 2.His contaminated suit could be contained in the airlock. Like a plastic bag of some sort. Possibly cutting the contaminated parts off to put in the bag.

James enters and the airlock is pressurized from the ships atmo while simultaneously being vented to space or a quarantined tank. It's essentially the same as the first, but the inner door is kept closed and would be safer if the valves that pressurize the airlock can keep the airlock air from backflowing into the ship. After enough time the hydrazine in the air would be vented or quarantined and James can enter.