What acceptable alternatives to trickle vents are available?
Since I am retired, this was something I had not heard of. It took me about 10 minutes to get a handle on the situation. Basically, it is an attempt to put a band aid on a problem the building regulations have caused. They seem to be using information supplied by ASHRAE, or the people that design, and influence sales of heating and air conditioning products, (In the name of our health), to make these regulations. 

If you do not have a super tight insulated new home, or are building one, it probably has enough inherent ventilation that you don't need trickle vents, if replacing windows in an older house. (?Why would you be replacing them in a new one?) I would agree they may be a good idea,--- if the windows came designed with them. 

I agree with you Iggy, I think bathroom fans and maybe kitchen ones, VOC, humidity operated, would be good, but those rooms need to be isolated to prevent that moisture from easily getting to other rooms. While it may be important, requirements designed by those with the most to gain from them, should not be the only ones considered for building regulations, and laws are not supposed to be made retroactive. 

Yes archess, you should indeed contact your building inspector and ask if you are required to comply, what alternatives are allowed, and most importantly, to explain why.