The government on Wednesday 14th July published its revised guidance on working safely during the pandemic in light of step 4 of the roadmap taking effect as of next Monday, the 19th July.
The direct link to the guidance can be found here – https://www.gov.uk/guidance/working-safely-during-covid-19/offices-factories-and-labs
Some of the guidance text has been simplified and there are revised/new parts contained within on ventilation and face coverings etc.
We would advise that it must be remembered that the devolved nations have some variations on guidance / rules. Any employee travelling to customers, suppliers etc. in any location other than England must be aware of and comply with those rules, as well as any rules set by the individual company(ies) they are visiting.