Cardiff University has denied taking what appeared to be drastic measures to prevent homeless people sleeping beside warm air-vents.

The university responded after claims “anti-homeless” metal cages had been installed outside a chemistry building, reminiscent of spikes that appeared in London this summer.

Student Lewis Hopkins blogged about the cages outside the Sir Martin Evans building on his daily cycle around campus. Hopkins was aware of the spikes in London and told the Guardian that “seeing a structure like this in person at my own university sickened me”.

He said the university was “further displacing these people and sweeping the issue of homelessness under the carpet” and that “perhaps a publicly funded institution should be more public spirited”.

Hopkins added that the homeless people “never caused any trouble, never littered nor gathered in groups. They were just content with finding a warm place to sleep at night.”

A Cardiff University spokesperson claimed that the grilles were erected “in the interests of health and safety” and that the intention was not to deter homeless people.

“The area covered by the safety grilles are not hot air-vents but boiler flue-vents, that can potentially produce products of combustion-diluted amounts of carbon monoxide being one of these as part of the diluted boiler flue gases.”

The spokesperson stated that the vents were considered safe in their normal use but “there could potentially be an increased risk if people are sleeping right next to the grilles for very long periods”.

They added that security had been working with the university to reduce the health risks to people sleeping directly in front of the boiler flue outlets.