How long to test kits last?

[Pillsbury]

I've had my green party test kit for as long as i can remember but i'm not sure if its still working? Its kept in the fridge but does it go off after time?

 

[Mazey]

E-mail the company and ask them !
[email protected] <[email protected]>

 

[Ernestrome]

I think they should be good for six months to a year, maybe a bit longer if refrigerated.

I think there are household substances you could use to check the reagent, but i can't remember any off the top.