Christopher,
While I am new to pressure washing I do know radios farely well
. I've never used radios on a PW job but I do use them in my other field of employment (EMS). I could not live without one.
Motorola's small FMRS radios are very durable and offer lots of accessories, but there are other good brands as well. I do suggest staying with a large company so that you can find the accesories you need. They also make waterproof carriers for the radios.
If you want a total hands free system then you want a VOX microphone to go with the radio. They turn on the microphone when you start speaking. Once you get used to them they are great.
The biggest thing to remember when you use a VOX unit is that you need to make a short humming sound before you talk or else the other end will not here the first part of your transmission.
Just remember that the FMRS radios are very common and cheap to purchase. Depending on you area, you may not be the only one on a specific channel. Most do offer 16 different channels to talk on so you may need to change channels if one is congested.
As for hearing on the job, most VOX units us an earpiece that picks up your voice through the ear canal as well as allows you to hear the other person. They do a farely good job of blocking outside noise on both recieving and transmitting
Good luck
Greg
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