public void updatePerm(double newPerm)
	{
		// adjust the permeability based on the temperature and pressure
//		double BP = getBPPres();
//		perm = ((pres-BP)/(maxPres-BP))*100/2;		// old, less realistic method
		perm = ((((maxPres-pres)/maxPres)+(temp/maxTemp))/2.0)*100;
		fixOutOfBounds();
		
		for(Molecule mole : getMolecules())
//			if(mole instanceof Water)
				mole.setPerm(newPerm);
	}