The Future is SENA – Intercoms for Work

So your Silky has just fallen out of the tree, or your rope tail is caught up on something on the ground, and your co-worker has just fired up the chipper. You’ve run out of small stubs to throw at them. So you will just have to wait.
Eventually, when the chipper is off, the saw is stopped and there’s a lull in the traffic, you can start shouting at each other… but it’s not long until noise drowns out your voices again.
That’s how it used to be sometimes, until I got my hard hats fitted with the Sena SMH10 Bluetooth headsets.
How good are they?

For most sites they are brilliant. You can communicate even when you’re a long way apart, or in such a noisy environment where even shouting wouldn’t have worked. With the headsets on you can talk in a normal voice, even with the saw or chipper going flat out. You can still hear if the climber needs you or you can warn a co-worker about something that otherwise would have meant leaping about waving your arms and whistling.

Signal strength is good for about 900m given a clear line of site. Sometimes, where there are large buildings between you, the signal can get crackly, but it is usually still possible to hear what’s being said. The microphone software filters out a lot of the background noise so that you can still hear normal talking and not just the machinery. The latest versions run silent until noise activated – so you needn’t hear every huff and puff from each other.

You can link your phone up to it and have a team of 4 (SMH10) all on the same channel. You can make or take phone calls while you’re sitting in a machine, hedge trimming or strimming.  You can play or share music and cut in at the touch of a button to communicate. You can connect to a crane driver, winch operator, tractor driver, etc or simply use it to help guide the reversing of the chipper up a tight driveway. Because it’s all mounted on the ear defenders, with the standard version, you can pop it on and off for use on different helmets.

What’s the battery life like?

Typically my battery lasts for 1 working day and most of the next. It depends on use; if you play music through it all day long I suspect it would be considerably less. So for a full day of site communications there is more than enough battery.

Will I break it? Technology that good will probably die in my hands!

Mine have been fitted to my hat for a year and are still going strong. Wet, cold and hot weather have not trashed them.

So they’re obviously awesome… anything bad to say about them?

Mine are side mounted on the ear defender brackets.  This has two down-sides.  Firstly, the ‘brain’ and its retaining clip are vulnerable to knocking against branches and unintentionally pressing the on/off button or falling off. Secondly, the model I have has the mic stem connected directly to the unit housing so you have to position it within reach of your mouth. If you knock the mic or move the mic stem it sends an unpleasant creaking noise to the others on channel.

To mitigate against these things I’ve fitted a piece of elastic over my ‘brain’ to prevent its accidental loss and I usually share some colourful language (without the need for shouting obviously) when a co-worker moves the creaking mic stem!  A throat mic fixable onto the chin strap would be a good option for arbs.

For a more long term solution it is possible to accessorise the system with an alternative mounting set up. Independent mic stems, connected by a wire, mean you can set the ‘brain’ out the way, somewhere rear of the hat and mount the mic and stem separately. The headphones need mounting inside your ear defenders, again connected by wire.

I’ve found it’s important to keep the terminals from the ‘brain’ to the mount clean. One of the 12 small pins on one of my sets got a bit gummed up somehow, but nothing a little lubrication and manipulating didn’t fix.

Ok…. How much?

Sena SMH10 and Sena SMH5 have different features and ranges. The SMH10 has a range of up to 900m, four way intercom and Bluetooth music functionality. The SMH5 has a range of 400m, one to one intercom and voice controls. They both have advanced noise control.

Sena SMH10 set with kit for 2 helmets at Treekit for £260+vat

Sena SMH5 set with kit for 2 helmets at Treekit for around £169+vat

You can join the SMH10 party with other existing users by buying a single SMH10 for one helmet for £138.60+vat at Treekit.

Additionally Treekit offer headsets already mounted into new ear defenders with or without a new hard hat.

Check out their website for more info and spec.

Marcus Undery