Sorry a museum of historic buildings or a museum in an historic building?

The Workplace (Health, Safety and Welfare) Regulations 1992

“workplace” means, subject to paragraph (2), any premises or part of premises which are not domestic premises and are made available to any person as a place of work, and includes— (a) any place within the premises to which such person has access while at work; and

(b) any room, lobby, corridor, staircase, road or other place used as a means of access to or egress from that place of work or where facilities are provided for use in connection with the place of work other than a public road

Now I suspect you may have issues if the building is listed with any attempt to install heating & ventilation and if sufficiently old with the activity being at unreasonable cost.

The Building Regulations are not retrospective and some of the newer regulations e.g. Construction Products specifically exempt the historic.

Hi Martyn

The definition in the Workplace Regulations includes the word "work" and as that is not defined in the Regulations you have to default to the definition in the parent legislation.

So, Section 52 of HSWA defines "work" and "at work".

In terms of case law, much of it is from long ago, and most of it is not specifically associated with H&S cases, but rather issues such as other employment rights. 

Unless your organisation doesn't think it employs anyone then it is going to have great difficulty in portraying the place where its staff do their daily tasks as being done in a "workplace" inside or outside (or both), and hence for an indoor (in particular) "workplace" they need to ensure that the workplace is at a reasonable temperature.

However, what might be "reasonable" will depend on many variables one of which is that the premises may be historic and subject to restrictions on what can and cannot be done in terms of installing "plant" (a term defined in Section 53 of HSWA) to heat or cool the "workplace".

....and when the parallel provisions of e.g. the Factories Act 1961 and Offices, Shops and Railway Premises Act 1963 were consolidated into the Workplace (HSW) Regs 1992, greater flexiibility was written in to what constitured a "reasonable" temperature in terms of a minimum.

Which means that you need to consider multiple variables including e.g. how long a person works in any area within a historic building and how easy it is for them to go to an another area to get warm (or cool).

Relying on the legislation isn't going to help you that much on this one.