Is an acrylic bath strong enough to stand in for a shower?

Hi there, 5mm acrylic baths are pretty sturdy but there is still flex in them when standing. You should ideally look for a reinforced one - various companies sell them under their company name with either 'cast' or 'ite' added to the word. For example Trojancast, Cliftonite, Bettercast and so on. These are usually 5mm but then have a sprayed lagging on them (feels & looks like fibreglass). This layer gives the strength required (some allege they're as strong as cast iron), and it also helps keep the water warmer for longer when bathing. These are more expensive than standard baths, but with some searching you can pick them up for reasonable prices, plus companies such as Trojan offer a 25 year guarantee with the bath. Kind regards, AC Plumbing (Sale, Manchester)