Questions tagged [safety]
The safety tag has no usage guidance.
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How does one post process in LS dyna for a seat belt?
Intro: I am looking to use LS Dyna to model a dummy crash.
I have done all the dummy positioning and set up but can not find any tutorials or info on the post process, boundary conditions and running ...
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Bending stress and permissible bending stress
I have a task to choose a material and gear module for a double step up gearbox with equal ratios
The first pinion has a max bending stress of 296 MPa and the gear has 239 MPa. The permissible being ...
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What properties are required for a safety window on a 10w laser enclosure?
What properties are required for a safety window on a laser engraver enclosure with a 10w diode based cutting head?
405nm wavelength
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Is a powder fire extinguisher not good for CRT TVs?
I'm about to buy a standard 6-litre powder fire extinguisher. However, in the description, they all say:
Suitable for [blablabla...] and for electronic devices up to 1000 V.
Up to 1000 Volts? But ...
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What standards or industry guidance define a top temperature for human contact to surfaces?
I'm looking for guidance to define how hot is too hot when related to human safety. I have heard of a general limit from OSAH of 60 °C (140 °F) being ok for contact up to 5 sec. Are there better ...
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Should I be worried about the "electron shower" I receive whenever I turn on my 1989 CRT TV?
If I stand in front of it when I press the "small power button" (the one which actually turns on the screen, as opposed to the big switch just giving the entire unit power), my big 1989 TV ...
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How realistic is the "death by CRT monitor" scene from Final Destination?
First of all, I realize that not only is this a fictional scene in a movie, but a movie (series) particularly infamous for its ridiculous, over-the-top death scenes.
Yet, I have heard of basically ...
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Is it really sane to drop buckets of water into a (CRT) TV on fire after unplugging it?
Today, I read this absurd (to me) claim on what to do if your TV catches fire:
Collect water and fill the unplugged TV. You can fill in only from the side. This is a necessary security measure. The ...
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Are these 33 year old cables inside a CRT TV dangerous/dying?
Today I finally opened up and dedusted my 33 year old TV, fearing both a fire hazard with decades of dust bunnies piled up in there (or so I imagined) and all sorts of possible non-lethal issues ...
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Can a nuclear reactor withstand a missile attack?
Because of the war in Ukraine I am interested in the question if a nuclear reactor is designed to withstand a missile attack.
In university, back in the eighties, we were assured that a nuclear ...
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HA and FTA, should a hazard analysis list one hazard for many causal factors, or several similar hazards for specific causal factors?
I'm getting into performing hazard analyses, loosely following MIL-STD-882E. To brush up on the subject, I'm reading through C.A. Ericson II's System Safety Engineering book. One thing I'm not clear ...
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Red Laser Safety Filters?
First of all, apologies if this is the wrong SE site.
Last year I bought a k40 laser cutter and it came with a square orange/red acrylic safety filter, which is meant to be used for looking through ...
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Is it somehow dangerous to spray compressed air into a CRT TV? [duplicate]
I am planning to unscrew the plastic chassis of my big old CRT TV, after having it unplugged for 24 hours, and then spray compressed air all over the internals to remove all the heavy layers of dust ...
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Why am I getting such conflicting safety advice regarding opening up and dedusting/servicing my CRT TV?
I have asked questions on Stack Exchange. I have watched many videos on YouTube. I have asked professional TV repairmen. I get wildly different advice on the safety of opening my 1989 28" CRT TV.
...
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Could large electromagnets be used to stop active shooters? [closed]
I was thinking that a powerful set of electromagnets in high risk doorways could be used to stop active shooters. By placing them in doorways. The magnet size could be mitigated. Also, they could be ...
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Is it dangerous for a child (or anyone) to bang away with a hammer and unscrew an old clothes washing machine?
In the mid-1990s at the latest, possibly something like 1992-1993, our family's clothes washing machine, presumably from sometime in the 1980s, broke down.
My dad brought it out on the driveway ...
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Fire safety assessment, event tree
For the following mathematical risk assessment assignment I have a question.
Assume that you need to make a decision on taking safety measures with
respect to a fire in a hotel due to an ashtray ...
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How dangerous is it for me and the TV to open up my CRT TV to dedust it with compressed air?
I've heard many times warnings about opening up CRT TVs on your own, because they contain scary old capacitors full of scary electricity, ready to zap your heart from you just looking at them.
But I ...
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How to protect users from shock hazards from electric vehicle high voltage system?
I am in the design phase of an electric vehicle. I have realised that at one point, we will need to implement protective measures to safeguard the users from shock hazards of the high voltage system.
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Historic tragedy: is this a drive belt accident?
My cousin turned up a chilling report of the death of one of our relatives in the Cyfarthfa steelworks in 1905. I'm trying to form a picture of just what happened. Sorry, I only have an image of this ...
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Why were handcuffs ever made with a chain between them?
I've noticed that modern handcuffs are always attached directly to each other, without any "chain" of any length in between. I guess I can understand why that make them safer and more robust....
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Why do I not get zapped when I hold my fingers on each end of an AA battery, like 3R12 ones?
When I was a kid, I got an 3R12 (or are they called R12?) battery. I don't know why, but I tried to put my tongue so that it touched both of the little metal things, which made it tingle. It felt ...
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Why are train brakes so complicated?
The concept is simple enough: no pressure in the train line has the brakes locked, full pressure is loose, and partial pressure drags accordingly. So if pressure is lost for any reason, the train ...
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Why do pneumatic valves need both a Safety Relay and an Air Dump to be safe?
If air dumps safely release pneumatic pressure from an industrial machine when an E-Stop is pressed, why is it also standard practice to cut electrical control power from the valves with a safety ...
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Is there any way to quantify the rate at which pressure is relieved in a reactor?
If a pressure relief valve is open, is it somehow possible to quantify the rate at which the pressure in the reactor will decrease?
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What is the purpose of these "safety" ledges on this Asian skyscraper?
While watching a video of a crazy person jumping around on buildings in some Asian country in a death-defying manner, I noticed these odd "safety" ledges outside, with nothing preventing you ...
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Lightning strike and metal structures in garden
I am worried about metal posts (support structures for plants) placed in garden and danger from lighting strikes. Posts are 3 meter long rebars and they are about 1,5 m driven into ground. Around ...
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Disposition of the generators on the shipwrecked Costa Concordia
Recently I have been reading about the shipwreck of the Costa Concordia, unfortunately what I read is not online, so I have no links, but it raised a lot of questions.
A rock hit by the ship tore a 50-...
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How to approach potential hazards that may result from user misuse, in a product design phase? [closed]
I am researching guidelines and considerations with respect to user safety when designing commercially sold products that contain user-operated machinery and moving parts (I.e. motors, pulleys, ...
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Why would an oxygen concentrator warrant an "Oxygen in Use" warning for firefighters?
I needed to use a medical oxygen concentrator for a short period, and I found it strange that it came with a warning label I was supposed to put in the window so firefighters would know it was there. ...
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Does electricity go through non-metal materials or not?
Ever since I was a little boy, I've always had this idea that electricity can only go through metal materials. For example, if I put a 100% metal screwdriver into the socket in the wall, I'm going to ...
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Safely Measuring Voltage from Solar Panels in an Experimental Research Field
I'm installing solar panels (not connected to the grid) in units out in a field for research we're doing that looks like this (this is an outdated image, but I can't find the updated one unfortunately)...
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Should we split a building containing a factory and a storage according to (NFPA 13) code?
I asking for a building that contains a desalination plant and a storage of water bottles (in carton boxes).
Should we split the factory and the storage or not (according to NFPA 13)?
And which ...
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What is this locking pin for a hinge called?
The following is a picture of a locking pin for a tubular hinge which specifies Maritime use. I assume it has something to do with railings but I'm thinking of fabricating my own similar hinges. "...
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Need advice on how to detect an object in the way of a closing door
I have a system design with a 149oz-in stepper motor for opening/closing a drawer style door. My cross sectional dimensions of the door opening are 20" width by 15" height. The motor ...
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Gas kitchen stove in skyscrapers
I have watched a property tour around an apartment in the Steinway Tower (NY) on YouTube and I noticed one detail that bugs me, namely gas stoves.
In Poland it is very uncommon for new blocks of flats ...
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How to manage two control loops as safety when BPCS is shared?
I am trying to wrap my head around some excerpts from:
CCPS Layer of Protection Analysis
CCPS Guidelines for Independent Protection Layers and Initiating Events
IEC 61511
I am trying to understand ...
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How is fire risk reduced in dense contemporary timber neighbourhoods?
In the Middle Ages most buildings were made from timber. After large fires timber was restricted or outlawed altogether and brick and stone became the preferred building materials, e.g. in London ...
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Can I safely cook on High temperature paint?
Like a million others, I have a set of enameled cookware that has seen enough use that the enamel has boiled, burned, or chipped off down to the cast iron substrate. Surprisingly, the outer painted ...
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Swing safety: maximum load of beam (supported at one end, free with load on the other)
My husband and his dad built a fort for our two boys. Coming off of one side of the fort is a 4x6 wooden beam with a tire swing attached at the end. It is supported on one side by the fort, but not ...
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H2 Sensor in N2 environment
We develop a test station where we might have H2 leakage.
To prevent explosion we are considering intertisation using N2 gas (primary explosion protection).
However we also want to detect leakage ...
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Is surgical and medical mask based on static electricity?
Is surgical and medical mask based on static electricity? By static electricity I mean like 3M N95 mask with at least two different layers of positive and negative static electrical layer. I googled ...
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Standards for safety car seatbelts locking condition
Is there an (international) standard which determines the condition when a car seat belt locks? Which standard is it? Does the standard determines a speed in m/s of the belt, such that it locks if ...
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What is the test procedures for a flame arrester?
A flame arrester is basically a heat exchanger in front of the tubulure. It conducts the heat of flame to some other place (to the liquid and/or the container especially if the container is built from ...
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Public data re possible estimate of baghouse efficiency. Plus characteristics of chromium emissions. Thanks!
I'm doing an article on a company whose Title V Operating Permit is currently under review by state regulators. (See biographical note below.) See also my specific questions, numbered below. Most ...
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How is it possible that it took until the 1950s or even longer before they started using car belts and neck-supported seats?
I've spent a large amount of my life thinking back on past times, both long ago and "recently", meaning ~1950s to me.
A lot of things make sense, but some things just fundamentally baffle me. One of ...
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How exactly do respirators seal out pathogens?
A "respirator with a rating of P100, has been tested to be proof against oil, and tested to filter 99.97% of all particles 0.3 microns in diameter or larger.'
As you know, an atom is 99.9999% empty ...
user24573
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How to remove protective valve cap from CO2 cylinder?
I have received a CO2 cylinder from an online seller fitted with a protective cap over the valve:
I understand these should unscrew, but this one appears to be stuck very firmly. Is there a standard ...
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Do pressurised cans still pose a risk to bursting in normal conditions, but after being exposed to heat?
We're planning on shipping some items from the US to Australia as you cannot get them here, that being:
https://www.chewy.com/sentry-stop-that-noise-pheromone-dog/dp/56486
I have been in contact ...
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Alternatives to sawstop technology
Sawstop table saw braking system works by putting a low voltage on the blade, and when it detects that voltage shorted to ground, the blade is retracted and slammed into an aluminum block. The claim ...
