Futon contained by front of radiator?

I just rented an apartment where on earth there is a wide open radiator under a skylight. I want to place a futon in front of the entire radiator separated by singular a few inches and had some question. Will this reduce the success of the heater? significantly? Will this be a potential see? Thanks in finance.
Where can you find those clear chairs that...
Answers:    It's not going to be a fire hazard or anything similar to that-we're not talking roughly speaking a red-hot radiator here...Ridiculous! But it WILL reduce the boil in your room significantly because radiators rely on convection currents to circulate the warmth around the room. The reason a radiator get so hot is because it needs to throw the warmth out across the room in this bearing and this cannot happen beside the futon in front of it.
Which one is better?
I grew up surrounded by an apartment that had a long monstrous gray radiator in respectively room, I think everyone surrounded by my apartment building had some sort of furniture surrounded by front of it to try and hide it. Some put the furniture a few inches away from it and others put the furniture right against it. We have it like that for 12 years, not a soul in the intire apartment building ever have any hazardous problems with it. And I don't consider it effects the heat, I know our apartment be always path too hot.
My window are 5ft soaring and 5ft cavernous....