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Sure, but COFF and its variations are much less practically common in Unixes (ie ignoring PE)

In any case, it’s highly doubtful being different from ELF is offering real value to anyone at this point, it’s just nobody wants to spend time, money, etc to migrate when incremental change to their own formats gets most of what they want.

Though it is probably accurate to say apple probably has it the worst here. Mach-O tooling is almost certainly the least available out of ELF, COFF, and Mach-O.


I honestly think Mach-O is more elegant than ELF, with its structure of load commands.

Of course, ELF still wins by being more mainstream, and not being de facto under the control of a single vendor.


> I honestly think Mach-O is more elegant than ELF, with its structure of load commands.

Can you elaborate on that, especially contrasting with ELF's PT_LOAD program headers?


I guess the distinction is, if Apple wants to add some brand new feature to Mach-O, they generally just define a new load command. There's generally just one way to do it. The main downside, is (in practice) only Apple can do it.

Whereas, with ELF – if you want to add a new feature, do you add it as a new program table entry type (PT_), or a new note type (NT_), or a separate note section (SHT_NOTE)?


Picardin is based on the chemical that makes black pepper spicy, which is why it does that if you get it your eyes or mouth.

DEET is a toluene derivative which is why it is super effective at melting plastics and doesn’t evaporate quickly

It was actually discovered by massive brute force chemical search for repellants


I always found DEET interesting because it is a toluene derivative, which is why it is remarkably effective at destroying plastics and such, in addition to being a repellant. Yet people spray it with abandon and then wonder what melted their watch or glasses or …

#1 is a bluff. It would be really hard to drag it out and judges hate that. You are much more likely to end up paying the costs of the little guy as sanctions than bankrupting them or whatever.

This is also straightforward enough and enough evidence exists that it would be hard to drag it out.


MMA is not very toxic. It has the same LD50 as vitamin C. Table salt and baking soda are twice as toxic as MMA, for example.

Additionally it is almost certainly not in vapor form at 100 degrees. In sunlight it will also polymerize to a solid pretty quickly.

As such you'd practically have to drink it inside to hit the ld50.

The explosion would be much worse than a release of liquid or vapor based MMA during the day, and here it almost certainly solidified at this point


MMA can apparently cause some issues that are more subtle than death. I would MUCH rather eat 1g of vitamin C than 1g of MMA.

Also, vitamin C is not volatile, so there is no risk of inhaling it as a gas.


Sure it can. So can Vitamin C though.

The overall point remains the same: the toxicity, both short and long term, of MMA, is comparable to lots of everyday substances that are both commonly eaten and inhaled.

It just isn't that toxic as far as chemicals go. That doesn't mean it would be like great for you but calling it "highly toxic" is tremendously overblown and doesnt serve anyone well to claim.

Let's save the highly toxic claim for things that actually deserve it. We don't have to sensationalize everything. I maintain my view that the explosion would likely be much much worse than the odds of significant respiratory damage from MMA.

Also note the sensationalization also causes placebo effect. People miles away started claiming "their lungs hurt" when

1. There was no leak

2. Even if their was and it was a conspiracy or whatever, your lungs have ~no pain receptors and your chest/pleura/etc would generally not hurt from MMA overexposure. Your throat would and your skin would, depending on concentration. But nobody complained about skin irritation when the is basically no way to end up with one without the other.

Etc.

Sensationalization of this hurt people so far more than the actual issue!


It produces highly toxic byproducts when it burns thus the exposure concerns.

Got a source for that? I searched a bit and found so evidence that its combustion products are notably hazardous. I did find an SDS stating that MMA’s combustion products do not have special hazards.

I do not! Sorry, digging stuff up is a chore. It's possible I confused it with a different acrylate molecule. However glancing at an MSDS for it gives me the impression that exposure can result in a variety of acute symptoms and is quite serious. It would appear to be a severe irritant with the potential to cause an allergic reaction. In general it seems like fairly bad news.

Given how toxic a number of the other acrylates are, how indiscriminate the chemistry of partial combustion tends to be, and how reactive MMA is, I would certainly assume the worst about burning it until proven otherwise.


MMA (this stuff) hardens when exposed to sunlight. The tank and valves are outdoors.

I would not be surprised to learn that is why the pipes/valves/etc are "gummed up" (to use the term from the article) - people who touch the valves/etc probably have mma on their hands/gloves, and then because those are outdoors, it eventually hardens.

Or something similar.


The standard choice for MMA processing is actually stainless steel, because carbon steel/iron/etc scavenge the inhibitor used to prevent thermal runaway. HDPE would work, and often how it is transported in drums, but for actual processing, everything would normally be spec'd as stainless steel.

Which, of course, is pretty spark resistant to begin with.

Even if this wasn't true, this is not a hard problem, you can use non-sparking tools, proper coolant, lots of things to avoid sparks.

Or you know, we could require that highly flammable materials subject to thermal runaway have "drill here in case of emergency" patch of non-sparking material or something.

The cost of ATEX/Class 1 Div 1 compliance would not really go up if you required this.


Inb4: I don't work in the industry, my knowledge is limited to a faint memory of a college course on fluid dynamics.

If I recall correctly, high pressure ignitable stuff can spontaneously turn !!FUN!! in absence of heat if it is suddenly relieved through a pinhole. Basically jet is followed by a ring-like zone where the stuff mixes with oxygen. Jet creates tiny zones of very high temp, thus igniting the mixture ring that follows.


This is true in other cases but in this case they are actually hoping it leaks


Maybe the thought process is that leak would effectively be pressure normalizing over a larger area and more gradually than creating a tiny hole, so whatever I said about jet ignition would not be applicable


So MMA has a fairly high autoignition temperature - it's >815F (gasoline is like 475F).

It also has a fairly small explosive concentration range (2-12%).

(the inhibitors it gets mixed with are about the same autoignition temperature, but have higher flashpoints).

In any case:

1. The pinhole issue can be resolved pretty easily by making a big hole instead of a small one :)

2. MMA is normally stored at ~0psi. The increasing pressure here is from runaway polymerization boiling the liquid (the runaway comes from the polymerization being strongly exothermic). These tanks are not built to handle very much pressure, usually a few psi max. I doubt whatever the tank pressure is currently qualifies as the kind of high pressure you are talking about.

3. There is apparently a significant crack now that is relieving most of the pressure. Which is preventing it from bursting. Assuming the crack didn't exist before this all occurred (so far the prevailing theory is it did not, but who knows how it will turn out), it almost certainly started as a pinhole that propagated, so if it was going to ignite the way you said, it would have happened already. My guess - even if what you say is 100% correct, the pressure is never high enough to cause issues, even with pinholes.


So random consumer who just bought a ton of batteries here: i don't follow the hype closely, nor am i a crazy battery dude, but i have tracked over the years the cost of doing battery backup vs generator, etc.

It's definitely the case for me (and friends of mine), that between reasonably priced batteries, inverters,etc, doing good battery backup for the house (and peak demand shaving/etc, i use a lot of power and take advantage of time of use tariffs) is now less than half the price of a generator.

Most of my friends spent 35-45k on a generator.

I will have spent <20k on batteries + inverters. It would actually be even less, but i have 600amps of split phase for the house, and 150 amps of 480v 3 phase for the shop, so i need two different kinds of inverters.

It is all literally being installed right now.

I would actually go completely off grid, but i live in a historic area and have slate roofs so can't really do solar easily ;)

As for what changed - 12 months ago this setup would have been almost double the price, just because of the availability (or lack thereof) of the right kinds of products necessary to achieve it. I know because i priced it :)

Availability here isn't in terms of stock, but literally in terms of "variety and choice of product".

For example - the availability of UL certified low cost 48v batteries in various sizes has skyrocketed in the past year. Lots of states require UL certification, assuming you are doing this in a permitted/etc way) Additionally, a lot more outdoor batteries are now available (my setup is outdoors but mostly protected).

The availability of choices in higher kVA but still residential grade inverters has also skyrocketed, etc.

As for why the price was doubled - before i would have needed 2x the number of inverters, and you really couldn't get a good 480v inverter except with high volt batteries that are wildly less available and wildly more expensive. On top of that, the batteries you could use that were UL certified and outdoor rated or could easily be done in outdoor enclosures was much lower than it is now.


> Most of my friends spent 35-45k on a generator.

Honestly curious: why do you need a generator ? And more to the point, why do "most of you friends" need one (35-45k seems like a huge investment, so it would not be some vanity purchase, right ?)

Is that customary where you live, because the grid is unreliable ?


It's fairly customary for folks who can afford it.

So, there are two issues:

1. The grid is now pretty unreliable. Georgia Power overall is a great company to work with (compared to say PG&E), but power quality has dropped out the past few years in some areas.

I've had plenty of equipment destroyed due to grid spikes and other weirdness that just didn't occur a few years ago. To give a concrete example: About 3 weeks ago, there were 4 days where literally every arc fault breaker in the house would trip randomly. Why? Because the incoming waveform became super noisy[1], and arc fault breakers are tricky beasts :).

They do notice and fix these things eventually, but the practical time to resolution is days, not hours.

2. We live in an area where the power lines are above ground and trees are aging out. They were planted over 150 years ago, and for a lot of these trees, the lifespan is 125-150 years. So we don't just get taken out by storms, but just nature :)

Georgia power puts new lines underground exclusively, and has moved a lot underground even around us, but our street is the last on the line of service that is both above ground and quite long. As a result, literally any issue/disconnect over about a 2 mile length with tons and tons of old trees, takes us out. This is also partially the reason our power quality sucks so much - any issue is more likely to affect us more than others.

Again - when it comes to outages they are quite fast at repair, having dismantled and removed insanely huge trees, and then repaired the line, almost always within 24 hours.

But it's still annoying. Combined with #1, it's just easier to be semi-off grid (IE monitor grid and swap over when grid is gone or sucking) with a generator or equivalent. Note that because we all own historic homes built in the early 1900's, our electricity usage is is significantly higher than normal just due to lack of insulation, etc. Retrofits only help so much for various practical reasons.

In a newly built home, the generator cost would probably be closer to 15-20k. Battery cost would be similarly half. Nothing to sneeze at, of course, but still.

[1]. I have a very high end fluke power analyzer (a fluke 1775) that i've had for years to debug power quality issues. These are power quality analyzers meant to be used to test service issues like this. I actually bought it when i got tired of having PG&E lie to me in California.


I would be interested in hearing more about the system you installed, if you don't mind sharing. I'll probably be taking the plunge in a year or two.


Bug me at my email, and i'll happily send you pictures/etc


An infinite number of comments about how good/bad/etc this is, and nobody seems to have noticed that it is literally a report of exactly one waymo getting stuck in flooded water that caused this.

I live in Atlanta. This was 3-4 inches of rain in 30 minutes, which is uncommon and was unexpected enough that the flash flood warnings were not issued until well after the flooding occurred.

The reporting doesn't mention it, because it doesn't fit the narrative, but does anyone want to guess how many human drivers got suddenly stuck in the flood?

I know it's more than 1 because there were 4 cars people abandonded on my street alone! I'm not even on that flooded or busy of a street.


> The reporting doesn't mention it, because it doesn't fit the narrative, but does anyone want to guess how many human drivers got suddenly stuck in the flood?

This is the important point here. Human beings are highly apologetic towards other human beings, but not so much towards machines. At the same time, the expectation towards machines is much higher.

Tells you more about humans than machines.


Comparing individual drivers to a taxi company is disingenuous and silly.

"How many taxi drivers got stuck?" is the actual comparison.

This is a paid taxi service. If I got an uncooked meal from a restaurant and their defense was that more people accidentally don't cook their food long enough than we do I don't think I'd be accommodating.


"How many taxi drivers got stuck?" is the actual comparison."

I would bet a lot of money the number here is also >1.


According to the timeline the account was suspended for 18 minutes total. That is fast enough that it could have simply been a bug in a Google rollout or something that made something think it was suspended when it wasn’t really.

If it was actually suspended the yeah it’s weird not to get an email.


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