Fire Suppression
You may be asked to turn your hand to many jobs, including:
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help fight the fire itself, with buckets, attached directly to the helicopter or on a long line

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move men and materials over natural barriers, between their camps and the fire

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scan with FLIR (Infra red)

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report fire dimensions back to the fire boss

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recover equipment afterwards

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search for hotspots

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do Initial Attack patrols

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Command and Control

Generally, what job you get is determined by the fireboss the night before (once the fire's organisational structure is in place) and you get your orders in the morning when you turn up for work.
Of course, what often happens is a system of organised chaos, where it’s hard to tell if anyone really knows what’s going on and you end up fighting a little bit all by yourself.
Otherwise, if you're not part of the operation, you should not be within 5 nm and below 3000 feet agl of the fire's limits. Anyone joining in should be in touch with the bird dog, if there is one—this is a light plane or helicopter used for air traffic and controlling the water tankers, and you need to be told when they are coming so you can get out of the way for 15 minutes or so.
If there is no bird dog, the local fire authority should have a UHF flight watch frequency, and the fire itself will have a common aeronautical VHF frequency allocated to it. Expect also to need a VHF FM frequency for the ground crews, which means you have to listen out on three very busy frequencies.
Water bombers will be used either to drop retardant or water, sometimes with foam. Retardant is phosphate fertiliser and water, with a dye so they can see where it hit. It is not actually used on the fire, but around it, so it is contained in a smaller area and allowed to burn out. Skimmers (like the CL415) pick water up from nearby lakes, but others get reloaded from nearby airstrips prepared for the purpose. There will often be dozers trying to create a break round the fire for the same purpose if it is small enough. Bombers do not usually get below 150 feet, as the water pattern will get disrupted, so your safest height is well below that, amongst the smoke, so be careful.
Helicopters also make use of handy sources of water, like swimming pools or small rivers, typically using the Bambi Fire Bucket. Such sources should ideally be close, upwind and at least the same elevation as the fire, so you don’t have to keep climbing with a load on. The Bambi can be transported at quite a speed (up to 80 kts), as long as you don’t pitch more than 15° either way.

These days, the minimum machine is likely to be the AStar B2, or a LongRanger with a good engine, with anything lower in performance, such as the 206, being relegated to observation or putting out hot spots, since the bucket size is only 90 gallons. In most cases, the killing time is between 30-45 minutes from the start of the fire, so, if you're on standby for Initial Attack, your response time should be as fast as possible (takeoff inside 3 minutes).