Posted By Stuart Nagle Steve. See Appendix 2 (page 38) of 'Safe Work in Confined Spaces' Confined spaces regulations 1997 ACoP. This refers to the relevant standards for manholes and other access openings to confined spaces and provides the relevant British standard numbers applicable. As far as manholes and entry points that are already insitu (e.g. old manholes etc in roads) these, as would all access ports etc, be part of the subject of a risk assessment prior to any entry (if unavoidable) taking place. If the access was so small as to severely limit access/egress and rescue in the event of an emergency, it may well be necessary to consider alteration/replacement to enable reasonable access/egress to the confined space. This is considered under the section in the CS regs on meeting the requirements of the CDM regs, both for new construction and improving existing structures. In addition to reading the CS regs, see details below. The standards quoted are: BS8007:1997 - Design for concrete structures for retaining aqueous fluids. BS5502:Part 50 1993 - Code of practice for design, construction and use of storage tanks and reception pits for livestock slurry BS8005 Sewerage Part 1 1987: Guide to new sewerage construction BS ISO 9669:1990 Series 1 freight containers - interface connections for tank containers Silos UK: Draft design code for silos, bins, bunkers and hoppers.

Posted By Oliver Whitefield Steve New manholes and the like which require man access are generally designed with a clear opening of not less than 675 by 675mm. Oliver

Posted By Ken Taylor I take it that, irrespective of what one calls the aperture through which one enters/exits, a confined space is still a confined space and the risk assessment approach should take into account safe entry, exit and rescue. 18" has been around for some time and was probably based upon anthropometrics. Seated audiences are to be afforded 450mm (18") seats where there arm arm-rests - although 400mm was used in the calculation for traditional bench type circus seats. However, with the increasing size of many of the population, I wonder how relevant these figures remain.

Posted By Ken Taylor I agree, of course, Stuart - and hence the need for assessment. I hope you don't think I was advocating the '18" idea' as I was simply suggesting where it may have come from originally.