Lone worker monitoring – Man down alarm – Advice and experience sought.

[Mr.B]

The atmosphere hazards exists in three areas:
1.
Rooms full of fruit such as apples, pears and kiwifruit (not in the same room of course).
The fruit causes elevated levels of carbon dioxide.
The digital readout of the CO2 level is on a display outside the room door.
We have protocols in place, that meet the Worksafe New Zealand standards, for how long a person is allowed in the room by what the CO2 % is.
Everyone also carries clip on gas detectors, marketing name is Gas Badge.

2.
Rooms full of apples where the atmosphere is deliberately 100% Nitrogen.
This is to keep the fruit longer.
Our friends from the Netherlands will know all about this. IIRC they invented the process for keeping tulips longer.
These rooms are sealed and locked. Nobody is allowed in.

3.
The plant and atmosphere generation service areas to supply the requirements of item 2 above.
This consists of two corridors 10m wide and 100m long, above the storage rooms.
The corridors contain the atmosphere feed and return pipes and large plastic bags called lungs, that hold Nitrogen in preparation for purging into the rooms.
There is an open vent at the northern end of each corridor and a fan that runs 24/7 in a vent at the southern end.
Continuous slow air exchange is maintained to avoid buildup of any leaked gasses.
The photo below gives half an idea of the working environment, showing the last 30m to the door. The lungs and BA sets are out of picture to the left.
I am unable to get a more recent photo just at the moment as we are in the middle of the apple season here and 'I want to take a photo' is not a good enough reason to go up there.

If the only hazard is a non-life supporting atmosphere, then supplemental breathing devices (commonly called EEBD - Emergency escape breathing device) should be a strong consideration on top of any communications, that way, a person or persons have a chance to save themselves.

To do any less is likely to be deemed negligent.

Each corridor has 11 such devices spaced at 10m intervals.

My personal opinion is that measures are sufficient if the company adopts a two worker policy.
However, my opinion does not count... It is up to the H&S committee.

[TerraHertz]

This video with Jeremy Clarkson illustrates the danger of low O₂
Towards the end he can't even concentrate enough to put his own oxygen mask back on.

Actually that was demonstrating high altitude effects, dropping air pressure while maintaining normal atmosphere gas ratios. At low pressure the body can't keep blood O2 saturation levels high enough. And they only took him a little way into the 'death zone.'

Something interesting we (Urbex group) found while doing group explores of underground spaces while carrying gas safety monitoring instruments, is that different people have quite different susceptibility to low O2. One time, while everyone else was coping OK (iirc the O2 level was about 16%) one of the group began vomiting, semi-coherent and nearly unable to walk. Time to leave.

[Lightages]

I have already stated my opinion, but I must again. This subject is very sensitive to me. I was a  health and safety representative for a union at a steel production company for 7 years. This stuff is not a joke and it cannot be considered discounted in any way. Any condition where a worker is exposed to hazardous conditions and is alone is criminal, period. There should NEVER be a situation where this should happen. There is no electronic solution to safety. You need two workers at least with one outside of the danger to monitor and call for help should a problem arise. There are many procedures to help ensure the safety of a worker. This is not rocket science and any company looking to replace proper safety procedures with an electronic device should be shut down, period. Nobody should need to be put into risk for the profit of a company. NEVER!

Two or three workers, plus proper emergency procedures to securely rescue anyone who is in danger is the first concern. Any other concern is money grabbing assholes trying to make money on the risk of someone's life.

Anyone giving suggestions here to help a company avoid their proper responsibilities should just shut up and stop giving vapid advice. It is dangerous and irresponsible. There are regulations and procedures for this.

People might think I am going over the top, but I have many stories. One for an example:

In the steel production plant where I worked, steel roils are flattened. The edges of these rolls of steel get wavy. To trim the edges there are rotary sheers that trim the edges and send the strips of irregular steel to a rotating spool to collect the trimmings. The trimmings vary in thickness and sometimes break. So the operator of the trimmer needs to go to the baler and re-connect the steel to the spool. This cannot be done while running as it is very dangerous to do so. Because of this, there is a dead man switch at the controls to prevent the operator trying to connect the strip while the machine is running. Well the operators learned to put a piece of steel on the switch to keep the trimmer running to make it easier to put the trimmed strip back on the baler.

The solution was to put another switch on the operators seat. They learned to put another weight on the seat.

The next solution was to put another foot switch. They put another weight on that switch.

One day a person died. A worker found the trimmer running and the operator nowhere in sight. There were three weights on all the dead man switches. He went to the baler room to look for the operator. I spoke to him afterward. This is his story to me, paraphrased.

"I went down to the baler and I saw that it was running. There was a really bad smell I had never smelled before. As I entered, I saw a stain of blood on the floor and a streak of blood from that stain. I followed the streak to the ball of steel winding on the spool. There was a bunch of guts and meat and bones sticking out of the spool of steel. I started to realize what had happened and started to feel sick. I followed the streak of blood back to the stain and then saw that near the stain was the head of my friend which had been popped off as the steel wound around the spool. I immediately went outside and started throwing up. As I was doubling over and throwing up, my boss arrived and asked me what was wrong. I tried to explain and tell him to not go in, but he did. He immediately came back out and starting vomiting beside me."

He was given 2 months of sick leave with counseling.

What is the point of this story? Nothing will stop the carelessness, or impatience, or complacence of a worker. There needs to be another person watching, or two, so that a worker will not take shortcuts or try to take that one chance. Devices do nothing. I have many other similar stories and a device can never stop a person from trying to please the boss, or prove their worth, or speed up their getting back to sleeping in their chair. Devices will never put on a Scott Air Pack and go in to rescue an idiot who wandered into an area with no oxygen. Anytime profit or personal reputation or pride are involved, idiots will kill themselves or companies will let them do so. This cannot be on the back of a simple device or devices.

I don't write this to impose my ego on anyone but rather for my concern for other humans and what I know and is more than evident. Stop this line of inquiry, it leads to nothing good.

[ed_reardon]

Another 'hazard areas' workers here.

What I have seen (and sorry I've no idea if it's available in NZ) from a company I work along-side is essentially an ID badge (it functions as an ID badge) worn on a lanyard around the operators neck, it combines as a help pager and 'man down' system.  Being worn as an ID badge it removes a lot of erroneous alarms as generally an ID badge worn around the neck is a difficult thing to hold horizontally for any period though daily activity.

It acts as a two-way coms device and the mic channel on the badge can be opened remotely by the control centre, as well as a panic button on the 'badge'. I believe the system can be set up so that it's either monitored directly by the company OR it can be managed by the supplier call-centre.

Me, personally,  I work in a two-man team where confined space entry is required, but the 'top man' is working at atmosphere outdoors so the top-man shouldn't be overcome by anything untoward; then a conventional set of gas-monitors,  escape BA for the operative 'in the hole' as well as a tripod rescue system constantly connected to the operator at risk.

[grumpydoc]

This video with Jeremy Clarkson illustrates the danger of low O₂
Towards the end he can't even concentrate enough to put his own oxygen mask back on.

Actually that was demonstrating high altitude effects, dropping air pressure while maintaining normal atmosphere gas ratios. At low pressure the body can't keep blood O2 saturation levels high enough. And they only took him a little way into the 'death zone.

Agreed, but it doesn't matter why the partial pressure of oxygen is low, the effect on your brain is much the same.

[German_EE]

Add one more vote for the buddy system, if it wasn't for that I would be dead or crippled. As for morons who disable safety interlocks, they deserve to be fired on the spot.

Any electronic devices should be an ADDITION to the above, not a substitute.

[tooki]

One day a person died. A worker found the trimmer running and the operator nowhere in sight. There were three weights on all the dead man switches. He went to the baler room to look for the operator. I spoke to him afterward. This is his story to me, paraphrased.

Thanks for sharing.

So lemme ask, what was the motivation for for workers to defeat every safety interlock that was put in place? It seems to me that the root cause of the problem was an incentive to not pause production for any reason.

[Lord of nothing]

Sorry i cant read every word in this tread...
I have some idas:
a) Take an Business Smartphone for example from Zebra, Honeywell, Panasonic (?),... the have some special App for Monitoring.

b) Take an Radio System. You might have have for a Freq. Licence.
Some Brands have Solution for like Motorola, Hytera, Kennwood,... (TYT but with there Radio is just a Self service)

c) You also could take the ascom i62 its the only Wifi Radio who I found.
Please note you need some licence or buy the "highest" Version for all Features!
And your Wifi Hotspot must suport the power saving features who are defined in a IEEE Standart if not the radio get very fast flat.

[Lightages]

One day a person died. A worker found the trimmer running and the operator nowhere in sight. There were three weights on all the dead man switches. He went to the baler room to look for the operator. I spoke to him afterward. This is his story to me, paraphrased.

Thanks for sharing.

So lemme ask, what was the motivation for for workers to defeat every safety interlock that was put in place? It seems to me that the root cause of the problem was an incentive to not pause production for any reason.

The motivations are always one of the following, laziness, frustration with a procedure not working, bad education in the dangers, pressure to keep production running, fear of being fired, and the worst is "I am too smart to need to follow the rules". In the case of this incident, probably laziness and "I am too smart to need to follow the rules". As I said, this is just one of many examples of why people need to watch people, not some dumb thing that can be bypassed, ignored, or can fail.

[TerraHertz]

Agreed, but it doesn't matter why the partial pressure of oxygen is low, the effect on your brain is much the same.

I wasn't disputing that, only making the point that they took him just a little way into 'too low'.
A more memorable video would be of someone suddenly breathing room-pressure air at less than 10% oxygen. They wouldn't notice anything at all, except after a few seconds they'd be unconscious. A few seconds more and they'd be dead.

Incidentally, this is also how people taking refuge in swimming pools from a bushfire, can end up drowned. Fire may use up most of the oxygen in ground level air, person in pool suddenly passes out, sinks and drowns.

[MK14]

Agreed, but it doesn't matter why the partial pressure of oxygen is low, the effect on your brain is much the same.

Incidentally, this is also how people taking refuge in swimming pools from a bushfire, can end up drowned. Fire may use up most of the oxygen in ground level air, person in pool suddenly passes out, sinks and drowns.

But could it also be too much carbon dioxide, which is heavier than air, so could collect in the pool.
Worse still Carbon Monoxide, which (even in low concentrations, I believe) is well known to gradually make people unconscious and worse.
Maybe that is why the following advises against it:

http://www.latrobe.edu.au/education/downloads/bushfire_safety.pdf

Taking shelter in pools, dams and water tanks is not a
safe option. The air above the water will be dangerous to
breath, and may be deadly when inhaled.

I guess they could be referring to carbon monoxide, carbon dioxide, other hazardous gases, or a lack of Oxygen. It is not clear to me which.