VEGETARIANS might be able to refuse to clean a fridge that stores meat and an environmentalist could be free to criticise a colleague who drives to work under guidance on how to deal with religion and belief in the workplace.

Employers should review workplace policies and practices to ensure that they do not unjustifiably discriminate against an employee who requests a change due to a particular belief, the Equality and Human Rights Commission (EHRC) has said.

The EHRC said this guidance applied to employees with a religion or belief which is "serious, genuinely and sincerely held" including druids, pagans, humanists and atheists.

Employers are not required to comply with all requests - such as time off for religious observance - but should "consider them seriously", the commission said.

They may be justified in limiting the freedom of employees in promoting their beliefs at work when this involves someone in a powerful position acting "inappropriately" towards someone in a vulnerable or subordinate position, the commission said.

Examples included that of a vegetarian who might be exempted from cleaning a fridge at work that has stored meat, where the impact on other employees can be easily managed.

An employer could be justified in rejecting a complaint from an employee who felt offended by an environmentalist colleague who had criticised people who drive to work on the grounds that this was a "reasonable expression" of a philosophical belief.

A Christian nurse might be able to offer to say prayers for a patient, the guidance said, where he had discussed and agreed this in advance with his employer that he could do so when the hospital chaplain was unavailable, to patients who had identified spiritual needs and who accepted the offer without any pressure or abuse of power.

But the commission advised that the law is "clear" that when someone is providing a public service they cannot, because of their religion or belief, discriminate unlawfully against customers or service users.

The guidance was issued to help employers comply with the implications of a European Court of Human Rights judgment issued in January on four cases brought by Christians over religious rights in the workplace.

The court ruled that Coptic Christian Nadia Eweida, a British Airways worker who was sent home from work for displaying a small silver crucifix during her job as an airport check-in attendant at Terminal 5 for the airline, had been discriminated against under freedom of religion laws.

But it rejected similar claims brought by three other Christians, including a challenge brought by nurse Shirley Chaplin, 57, who was switched to a desk job after she refused to take off a crucifix which hung round her neck.

Another two cases - those of marriage counsellor Gary McFarlane, 51, and registrar Lillian Ladele, 52, who objected to elements of their jobs which they felt conflicted with their beliefs - were also dismissed.

An EHRC spokeswoman said: "The commission does not make the law on what is or isn't a legitimate religion or belief. This is set by Parliament.

“It is important to remember that employers are not required to accept these types of request.

"The commission's role is to provide free, expert advice to employers helping them understand and deal with what can be complex issues, and helping them avoid potentially costly legal action."