Or doesn't have the kit to refill it (which most don't these days as it's not cost effective).
You can install powder indoors, there are some situations where it remains the best option weighing up all the pros & cons.
What the standard is saying is that it should no longer be a default option. This is primarily on health & safety grounds as:
- Discharging a powder extinguisher indoors will lead to rapid loss of vision as the area becomes 'powder logged' particularly if you don't have a high ceiling. This can cause disorientation, panic & can impede escape
- Whilst the powder isn't toxic it is classed as a respiratory irritant and is very unpleasant to breathe in even if in perfect health and you will cough and splutter, if there are any persons in the vicinity with pre existing respiratory complaints (asthma, COPD) the risks are greater
The other concern is secondary damage. The fine particulate nature of the powder itself causes issues depending on the nature of the equipment, items and areas in which it settles, this is further complicated by it's acidic pH and the fact it fuses and gets sticky when heated (which is part of it's extinguishing actions on Class A fires). Thousands of pounds worth of damage potential is there (& has been realised in the past)
If your risk assessment determines that the H&S and damage risks are tolerable in a particular situation that powder is appropriate then it can be used - the BS uses an example of a metal pencil sharpner factory where in the large open production area, the safety and damage risks are tolerable so they use powder to rationalise the number & type of extinguishers needed, but in the upstairs office areas they stick to separate water and CO2
Offices and shops don't really need powder extinguishers as the cons outweigh the pros, however in a very small retail/catering unit I supplied 2kg powders after giving the client sufficient information to make an informed choice and ensuring the commissioning paperwork made this clear.
Powder extinguishers will still be manufactured, there are far too many risks where it is the best or only realistic option.
By spinning a total load of rubbish on one hand and twisting some genuine guidance to suit the contractor mentioned would be right off my list of approved providers!