Cable supports designed for use in electrical and communications 'man-holes' may also be of use but they're normally VERY heavy duty and normally heavily galvanized against rusting and corrosion. I don't recall any colored supports or trays in my man-hole / person-hole days but my years in man-holes were mostly in the sixties during my apprenticeship before theatre rescued me from the trenches, literally.
This stuff wouldn't likely be anything you'd ever be looking for but Hubbell lists it as still being available from the days of pulling in 3 conductor/ 3 phase 13K8 and 27K6 Volt stranded copper 350, 500, 750 and 1,000 MCM lead sheathed high voltage distribution cables. (Back in the days when 'men were men' and apprentices [such as myself] were too naive to know better.) Among the specs were how many pounds the various cables weighed PER FOOT. I recall Mathias Klein having a line of these supports as well. In my limited experience of about a year in tunnels and man-holes, we were normally securing these brutally heavy cables to the poured concrete ceilings of underground tunnels and resting the cables on wall brackets within man-holes where splices and 'T' and quad taps occurred. The idea was to keep everything high and dry in the event of underground flooding. My best memories of my tunnel dwelling days were they were naturally comparatively warm in winter and cool in summer (and definitely out of direct sun light) We'd arrive dressed for a Canadian winter and doff our heavy outer garments within 25' of an entry hole. Perhaps dash out for the coffee trucks but not put our heavy coats back on again 'til quitting time for the lengthy trudges above ground back to our parking locations.
