HR directors may be underestimating the potential business impact of foreign employees' ability to speak the language.
This is according to research by the London School of English, which found that 98% of HR directors believe that their non-native English speakers can communicate effectively.
However, Hauke Tallon, director at the London School of English, said that this did not take into account the need for specialised vocabulary or the toning down of foreign accents that could cause confusion or misunderstanding among colleagues or customers.
"It's surprising that HR directors are so confident in the abilities of non-native English speakers who, when working in specialist professions, often need training in the specific vocabulary, phrases and jargon used by these professions in the UK," he said.
"The English language is full of complexities and nuance which can impact on understanding, particularly in professions which interact with the general public."
More than half (52%) of HR directors polled said that they did not believe that English spoken with a strong foreign accent would affect understanding, while a further 69% said that they would not consider training to soften a strong accent.
"With the right training, it takes surprisingly little effort for someone with a competent grasp of English to soften their accent," added Tallon. "This could make the difference between clarity and confusion."
The survey also found that 78% of HR directors did not believe it necessary to train English speakers to moderate their vocabulary when communicating with non-English speakers, while 4% thought that speaking "more loudly" would help to get their message across.
The research comes as a House of Lords committee claimed that foreign doctors and nurses who cannot speak English well are a risk to patient safety.
The Social Policies and Consumer Protection EU Sub-Committee wants bodies such as the General Medical Council and the Nursing and Midwifery Council to be able to test the ability of all non-UK applicants to speak English before being allowed to work in UK hospitals and practices.
Currently, only those originating from outside the EU are routinely tested, but health secretary Andrew Lansley told the Conservative Party conference earlier this month that he intended to extend this to all doctors who were trained overseas.
The issue of doctors' language abilities and skill levels has been in the spotlight since the death of 70-year-old David Gray in 2008. An inquest ruled he was unlawfully killed by German-trained Dr Daniel Ubani on his first shift in the UK as an out-of-hours GP.