Wow! Wiretapping? Surveilliance? I have had an open relationship myself for two years time, after being not only swingers for five years but also as managers of a local swing club. Add talking to/counseling about literally 1000 kinky/crazy couples, I still find that WAAAAY overreactive and completely unrealistic on your husband's part. And I mean fundamentally so. Even if you have Master/sub relationship, (not mentioned in your post) it's obvious you are uncomfortable with any of his actions as a result.
Open relationships are two sided. Period. Will a woman possibly have more men to choose from than a man will have women? Very likely. Even a (frankly) ugly woman has about a 1000 to 1 ratio compared to what even a good looking, stable man has when being able to choose who she/he sleeps with during an open relationship. My own goes like this, talk with a woman online every day for a month. Say the smallest wrong thing before she is comfy enough to actually meet me. POOF! Magically gone. My female partner goes online for ten minutes. POOF! Magically 10 men she could sleep with if she chooses, THAT DAY alone. However, let me "advertise" my skills with another woman or two in the group room of a club, and I get more action then she does. I've certainly have had jealous husbands ruin my night too, in all seriousness. My point? A woman has to know you before she'll just roll over and open wide for a man. Most men don't take enough time to care ask anything about her, (limits, boundaries) before they'll sleep with a woman.
This could be very likely the cause for your husband's somewhat unfounded jealousy on his part. You may have it better in one or both ways. Worse, he doesn't have to see it to believe it. He will never get the same in return as far as frequency or numbers of partners. Or maybe he hasn't found near the woman/women that you found in your own explorations with another man/men. You may have gotten lucky with finding a partner you really like sexually. If not, you can always move on to another man. He may not have that easy of a choice with another woman. It's a simple fact that he has to live with if he wants to play this game. Easy to say, just harder to actually discuss.
He also may not want to lose you to someone he thinks can do you better than he can. Big issue right there in itself. Fragile male ego might need a Band-Aid, as ridiculous as that may sound coming from a guy.
Still, is any of this justifcation for limiting you from seeing other men? No. Nor for wiretapping and surveillence on you. He needs to seriously ask himself why he is with you if he doesn't trust you enough to take your word that you aren't doing anything. If by any means you are doing something on the side, without his knowledge, I'd stop immediately. We don't want to hear about you being killed or seeing you on an episode of "Cheaters" on TV.
So. Should you stand for it? Hell, no. Stop everything. Now. No more explorations for him either. This isn't a simple issue of separate room/full swap petty jealousy (any beginner swinger knows how that gets) any more, but a core issue of your relationship as husband and wife.
Clearly, some hardcore discussion is needed. If he does reject the idea of stopping himself, put on the brakes, parking, emergency, put your feet through the floor, whatever that stops this runaway train. Follow through.