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Safety Program for a County Wastewater System

01799068 — Wed, 16 Jan 2008 13:14:29 GMT

We are looking for help in developing a Safety Program specifically for the Wastewater Department including Operations, Maintenance, and Collections. Our system has 2 large plants (6mgd and 10mgd) and 6 smaller (less than 100,000gpd) satellite plants. Does anyone have a safety program they could email to us to get us started in the right direction?

RE: Beryllium control plan

Dedalus — Thu, 29 Nov 2007 09:28:02 GMT

You need to be a bit more specific...do you mean the removal of Be from wastewater? The management of Be solid waste? Handling Be in a manufacturing environment, safely?

Beryllium control plan

David1205754 — Fri, 23 Nov 2007 07:40:44 GMT

Dear All,
I need to write a control plan regrading the beryllium which is dangerous for human health. Does anyone have such kind of handling experience or reference?
Thanks.

RE: Vaccinations

Old lag — Wed, 21 Nov 2007 14:11:33 GMT

Obviously not written by a lawyer either -- too many words under three syllables.

Vaccinations

SueKrueger — Wed, 07 Nov 2007 12:48:46 GMT

I'm looking for feedback from other treatment plants / collection systems regarding what vaccinations, if any, are provided by the employer. Of these, are they mandatory or optional?

RE: Vaccinations

D Shulmister — Wed, 21 Nov 2007 13:40:05 GMT

Obviously not written by a politician -- too many words over three syllables.

RE: Vaccinations

Dennis — Wed, 21 Nov 2007 03:36:29 GMT

I wonder how many use this as a guideline? The wording is pretty vague or generalized, in my opinion... some lawyer or politician must have written it. Vaccinations are cheap (or free), why take the risk even if "very slight or extremely remote"? I'm thinkin' C.Y.A., eh?

D Shulmister (11/7/2007)

From California:

a. Recommended

Tetanus-diphtheria (Td)....All adults, and especially sewage workers, should be up-to-date on Td immunization. For those who have completed the basic series of three immunizations, a booster should be given every ten years.

No other immunizations are routinely recommended at the present.

b. Not Routinely Recommended

Poliomyelitis - Sewage workers are at very slight risk of vaccine polio virus exposure but at virtually no risk of wild polio virus exposure. No cases of occupationally acquired paralytic poliomyelitis in U.S. sewage workers have been documented since polio vaccine came into widespread usage.

Typhoid Fever - The risk of this disease for sewage workers in California is exceedingly small. Only one case has ever been reported in a California sewage worker and this was in an individual who had received at least one dose of typhoid vaccine nine months previously.

Immune globulin (IG) and Hepatitis A Vaccine - Routine hepatitis A immunoprophylaxis is not recommended due to lack of evidence of significant occupational risk for sewage workers in this country (MMWR 1996; 45 No. RR-15).

Hepatitis B Vaccine - While blood and other body fluids (e.g., menstrual discharges, etc.) enter the sewage stream, hepatitis B virus is present only in very dilute concentrations. No cases of hepatitis B have been linked to sewage exposure in the U.S. Moreover, since hepatitis B is not transmitted by the fecal-oral route, there is little risk from municipal sewage.

Cholera - The risk of cholera for sewage workers is extremely remote. Only a few cases of imported cholera are reported each year in California and there has been no secondary transmission. Vibrio cholerae concentrations in California sewage are so dilute as to probably be non-infectious. (Whereas 102 Shigella are needed to cause disease, as many as 106 to 108 V. cholerae are needed.) Even if cholera did result, specific treatment is readily available.

Finally, a word about HIV and the risk of AIDS from sewage. The remarks made above about hepatitis B, and its extreme dilution in sewage, apply to HIV as well - except that the level of HIV in sewage would be even several orders of magnitude less than that of hepatitis B. Moreover, like hepatitis B, HIV is not transmitted by the fecal-oral route. Thus, the risk of hepatitis B from sewage is virtually non-existent and the risk of HIV transmission from sewage is even less.

Reported by: Immunization Branch, Division of Communicable Disease Control, California Department of Health Services.

RE: Vaccinations

Sabir — Sat, 10 Nov 2007 02:09:42 GMT

Visit the link below, it is intrested to note that the requiremnet for WWT plants are relatively simple.

http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=25898

RE: Vaccinations

Dennis — Thu, 08 Nov 2007 21:32:40 GMT

We offer Hep A&B vaccinations. The employee must sign a waiver if they refuse.

RE: Vaccinations

D Shulmister — Wed, 07 Nov 2007 13:34:45 GMT

From California:

a. Recommended

No other immunizations are routinely recommended at the present.

b. Not Routinely Recommended

Poliomyelitis - Sewage workers are at very slight risk of vaccine polio virus exposure but at virtually no risk of wild polio virus exposure. No cases of occupationally acquired paralytic poliomyelitis in U.S. sewage workers have been documented since polio vaccine came into widespread usage.

Typhoid Fever - The risk of this disease for sewage workers in California is exceedingly small. Only one case has ever been reported in a California sewage worker and this was in an individual who had received at least one dose of typhoid vaccine nine months previously.

Cholera - The risk of cholera for sewage workers is extremely remote. Only a few cases of imported cholera are reported each year in California and there has been no secondary transmission. Vibrio cholerae concentrations in California sewage are so dilute as to probably be non-infectious. (Whereas 102 Shigella are needed to cause disease, as many as 106 to 108 V. cholerae are needed.) Even if cholera did result, specific treatment is readily available.

Finally, a word about HIV and the risk of AIDS from sewage. The remarks made above about hepatitis B, and its extreme dilution in sewage, apply to HIV as well - except that the level of HIV in sewage would be even several orders of magnitude less than that of hepatitis B. Moreover, like hepatitis B, HIV is not transmitted by the fecal-oral route. Thus, the risk of hepatitis B from sewage is virtually non-existent and the risk of HIV transmission from sewage is even less.

Reported by: Immunization Branch, Division of Communicable Disease Control, California Department of Health Services.

RE: Wastewater Plants and Bad Air Quality Links to Cancer or Bladder Cancer?

D Shulmister — Wed, 07 Nov 2007 13:21:23 GMT

prose (11/7/2007)

As for your sincere sympathy perhaps if we saw it displayed at the funeral, oh wait you were not there, nor were any of the other employees for fear of losing their jobs. No need for a response Supreme Being, I'll never log back in to read it.

No, I was not at the funeral. Your dad was still working there when I left. I did not hear of his passing until some time later. Your sarcasm is misdirected.

Wastewater Plants and Bad Air Quality Links to Cancer or Bladder Cancer?

primey — Tue, 03 Jul 2007 22:44:38 GMT

I have a friend who works in the WasteWater Industry who has been diagnosed with Bladder Cancer is it likely the toxins we breath in this Industry may have caused this to form? I would appreciate any information and expert advice. Thanks for your time and thoughts and input.

RE: Wastewater Plants and Bad Air Quality Links to Cancer or Bladder Cancer?

prose — Wed, 07 Nov 2007 12:23:22 GMT

First of all thanks for the anonymity, I'll show you the same respect. Secondly, when dealing with the nature of wastewater management, the city, the government et cetera there will obviously never be a link to cancer or any disease that may or may not be killing the employees, not to mention that the residual effects may not occur until years after their employment has ended. Unless of course people are dying in record numbers in one specific area. As for your sincere sympathy perhaps if we saw it displayed at the funeral, oh wait you were not there, nor were any of the other employees for fear of losing their jobs. No need for a response Supreme Being, I'll never log back in to read it.

RE: OSHA to cover state and local governments?

John Sansalone — Thu, 01 Nov 2007 19:39:51 GMT

The original OSHA law specifically excempted state and local employees ( I'm guessing to prevent the appearance of usurping States Rights, etc., though it made no logical sense from a purely safety perspective). Over time, some (most ?) states adopted the OSHA standards as being applicable to the excepted employees. In N. Y., it took about 10 years, and the creation of a state agency (PESH - for Public Employees Safety and Health). The OSHA standards were adopted by reference.

Don't know why this bill now. Perhaps there are some states that never adopted any such standards, and with the liability issues these days, and concerns about anthrax, resistant strains of various bugs, health care as a national issue, etc., maybe the Feds. just decided to do away with the patchwork approach. Assume that public employee unions are supporting it as well.

Would be interested if anyone else knows anything about this.

OSHA to cover state and local governments?

Dennis — Wed, 31 Oct 2007 20:32:53 GMT

I heard about this yesterday and thought I'd do a little research to verify.

A bill has been introduced in the House of (so-called) Representatives that would "amend the Occupational Safety and Health Act of 1970 to provide for coverage under that Act of employees of State and local governments."

The bill # is HR 1517. I copied the text below. (It's short and to the point). A little deeper research shows that the bill was referred to the Subcommittee on Workforce Protections on 6/27/07.

I tried to add a link but it wouldn't work for some reason... You can do a search and find it easily.

(Could this be pending election results in 2008)?

Any thoughts on this?

-------------------------------------------------------------------------------------------------------------------------------------------------------------------

110th CONGRESS

1st Session

H. R. 1517

To amend the Occupational Safety and Health Act of 1970 to provide for coverage under that Act of employees of State and local governments.

IN THE HOUSE OF REPRESENTATIVES

March 14, 2007

Mr. ANDREWS (for himself, Mr. GEORGE MILLER of California, Ms. WOOLSEY, Mr. BISHOP of New York, Mr. PAYNE, Mr. HARE, Ms. SHEA-PORTER, and Ms. CORRINE BROWN of Florida) introduced the following bill; which was referred to the Committee on Education and Labor

A BILL

To amend the Occupational Safety and Health Act of 1970 to provide for coverage under that Act of employees of State and local governments.

Be it enacted by the Senate and House of Representatives of the United States of America in Congress assembled,

SECTION 1. SHORT TITLE.

This Act may be cited as the `Fairness for State and Local Workers Act'.

SEC. 2. COVERAGE OF STATE AND LOCAL EMPLOYEES.

Section 3(5) of the Occupational Safety and Health Act of 1970 (29 U.S.C. 652(5)) is amended--

(1) by inserting `including a State or political subdivision of a State,' after `employees,'; and

(2) by striking `or any State or political subdivision of a State'.

RE: 24" Emergency Pressure Relief Valve on Anerobic Digester

Dookie — Thu, 01 Nov 2007 18:59:01 GMT

You need to have a talk with the operators. Have any of them experienced a anerobic digester go off after sucking in O2 from neglect or????

24" Emergency Pressure Relief Valve on Anerobic Digester

01617105 — Tue, 29 May 2007 12:26:51 GMT

From time to time anaerobic digesters with concrete roofs build up pressure and the roof is damaged when the pressure is relieved. Our digesters have two 6 inch pressure-vacuum relief valves on them. Sometimes operators overfill the digesters and plug up the flame traps under the relief valves. This allows pressure to build up cracking the roofs, blowing off access covers and lifting the roof to allow sludge to escape between the wall and the roof.

Groth and Varec make a 24" hinged manway that is weighted so it lifts and releases the sludge or gas that is pushing on it. It is called an emergency Pressure Relief Valve. I know a 24" opening will not plug.

Is anyone using these on concrete anaerobic digester roofs?

RE: hard hat help!

Dennis — Thu, 01 Nov 2007 11:03:15 GMT

Even if there weren't any 'external' guidelines, it could be put in to a company safety policy or standard operating procedure. Good luck, be firm. Being the 'safety person' isn't always a fun job!

hard hat help!

Fern — Wed, 29 Aug 2007 18:11:54 GMT

Hello everyone, I am new to the safety game, and well Here where I work the last safety man had been let go. So safety had not been enforced within the past 4 years. Crazy huh? Anyway I came in now to try to clean up the plant "mess"and one hurdle I came upon was that many employees here where operating overhead shop cranes, jib cranes etc... without a hard hat. Their reason for not wearing one when approached was "why should I?" The rules were of course not enforced by supervision. My question is Where in writing is their a law or osha rule stating how many inches or feet should an object be over one's shoulders/head for the employee's to wear a hard hat while operating a crAne? THe old rule here is one should have one on within a five feet radius of operating A crane regardless of how high load is lifted. But I want to rephrase that policy with detail. HELP!

RE: Wastewater Plants and Bad Air Quality Links to Cancer or Bladder Cancer?

D Shulmister — Wed, 31 Oct 2007 10:04:20 GMT

Chuck was one of the most pleasant people you'd ever want to meet. His death was a tragedy and also a shock to me. It was discovered that the reclaimed water had been cross-connected to the potable supply at Albert Whitted. However, there were several homes in the City that had potable lines crossed with reclaimed and used for drinking for several months. None of the residents suffered any ill effects to my knowledge.

During his employment, the only chemicals used were liquid chlorine for disinfection and polymer for sludge processing. Ortho-tolidine was not used to determine residual chlorine, and the sludge processing was seperate from the plant operations. Hydrogen sulfide is always present around wastewater plants, but universal exposure suggests no general connection with operator sicknesses.

As far as Hep C infections, I never knew any of the operators were infected. Like HIV, Hep C tends to be an infection transmitted by blood-to-blood contact, non-sterile needles and dental equipment, and etc. Its major effects are on the liver.

Other operators in the system have passes away due to cancer, but none could be linked to employment causes. You have my sincere sympathy.

RE: Wastewater Plants and Bad Air Quality Links to Cancer or Bladder Cancer?

prose — Tue, 30 Oct 2007 12:18:22 GMT

You're exactly right, it was not only the sewage. It was the needles, feces, used condoms (the list is endless) which first wash into the plant, together with the chemicals, insects and the sewage itself. These people are exposed to endless contaminations from heavy rains (washing in with pesticides) to the constant acrid odor that they are inhaling everyday. I cannot tell you how much backing we had from the other employees, (who now have been diagnosed with Hep C) until they were told they would lose their job. I'm not a huge conspiracy theory person, but this I witnessed firsthand. Believe me, none of them drink water from the sink! As far as my dad's immunity, unfortunately like I previously stated, he worked all of the overtime hours he could get, holidays, etc... he was an avid jogger, and a healthy eater that never had any real health issues prior to 1996. How many times has a cross contamination happened and the public was never notified? We'll never know.

RE: Wastewater Plants and Bad Air Quality Links to Cancer or Bladder Cancer?

Dedalus — Tue, 30 Oct 2007 10:58:25 GMT

One chemical that's been definitively linked to cancers of the bladder is o-tolidine, that color reagent used to test for residual chlorine. White (Handbook of Chlorination) suggests finding alternatives and I agree.

Liver diseases are also known to be linked to the development of certain cancers.

My sympathies on the loss of your father, Prose.

"Guys and Gals, use your PPE's"

That is always sound advice. And, wash your hands a lot.

RE: Wastewater Plants and Bad Air Quality Links to Cancer or Bladder Cancer?

Jerry — Mon, 29 Oct 2007 17:20:50 GMT

People with low immunity may have a problem with some diseases if they come in direct contact. However, historically, the diseases you mention are rare in the wastewater field. I've never heard of a cancer case caused by sewage. Maybe this was caused by the chemicals used in treating the sewage. Warmer climates and conditions in sewers can promote pathoginic growth.Some polymers, and disinfecting chemicals are known carcinogens and can possibly cause health problems. A lot of these chemicals are already in your drinking water. So the possibilities are endless. That's why it's almost impossible to prove in court, or get a handle on a contaminate source.

Guys and Gals, use your PPE's

RE: Wastewater Plants and Bad Air Quality Links to Cancer or Bladder Cancer?

prose — Mon, 29 Oct 2007 14:44:10 GMT

My dad was working for the plant near Albert Whitted airport which is the one we believe where the exposure was the greatest. However, he also (primarily)worked for the 62nd Ave plant, in St. Petersburg which is where the Hep C cases have been reported, and other illnesses amongst the workers.

RE: Wastewater Plants and Bad Air Quality Links to Cancer or Bladder Cancer?

D Shulmister — Mon, 29 Oct 2007 11:24:05 GMT

prose (10/26/2007)

We tried unsuccessfully to sue the city he worked for however it is a tough case to prove especially with little monetary backing.

Even with a lot of monetary backing it's a tough case to prove. Which utility was your dad working for?

RE: Wastewater Plants and Bad Air Quality Links to Cancer or Bladder Cancer?

prose — Fri, 26 Oct 2007 16:28:52 GMT

My dad was a wastewater operator in Florida for approximately 15 years. He was diagnosed with a 20lb abdominal tumor (perfectly encased in a hard shell) in 1996. The tumor was removed. In 1997 he was diagnosed with a brain tumor, which was once again removed. Shortly thereafter he was stricken with another bizarre abdominal tumor (18 lbs) which eventually took his life in 2001. All of the types of cancer with which he was diagnosed were known to be environmentally derived. My father worked overtime hours, weekends et cetera and was on a regular basis exposed to all of these carcinogens with little protection. We tried unsuccessfully to sue the city he worked for however it is a tough case to prove especially with little monetary backing. Do we believe all of the cancers were environmentally related? Without a doubt. They have changed several policies since his death, however we are aware of several cross-contamination instances in which the public was never informed, and all of the workers drink bottled water. Moreover, through one co-worker we have learned some time ago that several of the employees (approx 6 out of 10) have been diagnosed with Hep C. It is definitely a dangerous occupation and the potential for serious illness is extremely high. Good luck to you and your friend. I wish you the best.

RE: Use of IPODs in Labs

MR_HOLMES — Tue, 16 Oct 2007 13:05:51 GMT

I am with you. We sometimes blast the music loud enough to wake the dead. It is embarrassing when customers come in but we have fun anyway.

I think this issue is more about group dynamics and social norms than safety.

Use of IPODs in Labs

JeffMacDonald — Sun, 23 Sep 2007 22:39:10 GMT

I work in a fairly large (17 analysts, plus management & support staff) wastewater lab. I am more or less a group leader and have no supervisory authority. Some coworkers wear IPODs while performing lab work. I feel that, at a minimum, this impairs communications. More importantly, I think there is a safety issue with the wearing of these. As an example, as I was warning a coworker that an autoclave cart was hot, she reached out and touched it. She was not really burned, but perhaps we were just lucky on that occasion. Lab management has observed analysts wearing IPODs in the lab setting and (to my knowledge) has not said anything. I feel that banning these devices from the lab would be appropriate. What do you think?

RE: Use of IPODs in Labs

GaryS — Tue, 16 Oct 2007 11:40:56 GMT

I'm in the minority here, but I don't see it any different than listening to a radio. You can turn either too loud to the point of distraction. I typically use my ipod in our cube farm, loud enough to reduce distractions around me, but low enough that I can hear conversation if anyone pops their head in and asks a question. (and yes, I remove the earbuds for a conversation)

If you walk by someone and can hear sound from their ear buds, or if you call them, and they don't hear you, then yes its time to turn it down. Otherwise, it shouldn't be a problem.

RE: Use of IPODs in Labs

MoscowLabAnalyst — Mon, 08 Oct 2007 12:44:56 GMT

MR_HOLMES (10/5/2007)

Wearing earphones while driving legislation was passed not because of any accidents but because of paranoid politicians that have nothing better to do for our community than make laws that don't truly improve our surroundings. I am sure if we put our collective heads together we could make better laws.

I agree that there is a small amount of risk in allowing some lab employees to wear earphones.

...I am not convinced that the ipod had anything to do with the accident. The same things could easily happen to any untrained worker or irresponsible cyclist.

I really want to understand this issue out of respect for my fellow coworkers.

I think that your desire to really understand this issue is thwarted by your unwillingness to be convinced by any amount of evidence that diminishing one's ability to hear one's coworkers, whether or not they are boring coworkers, is unwise. Deaf people use special devices to compensate for their loss of hearing.

The original quote is much better, but to paraphrase someone who has experienced both: "Blindness will disconnect people from things, But deafness disconnects people from people."

RE: Use of IPODs in Labs

Victor — Fri, 05 Oct 2007 12:43:16 GMT

People that wear iPods while performing any type of activity other than standing in place need to receive the Darwin Award. I'll one up you on the "burning iPod" and parallel it to the idiot golfers that play while a thunderstorm is wreaking havoc the course. Use the following links to access PDF reports put out by New England Journal of Medicine. People getting struck by lightning while wearing iPods:

Thunderstorms and iPods: Not a Good Idea

RE: Use of IPODs in Labs

Bill Gaines — Fri, 05 Oct 2007 11:46:16 GMT

And now for the icing on the cake: http://www.breitbart.tv/?p=6412

RE: Use of IPODs in Labs

MR_HOLMES — Fri, 05 Oct 2007 10:56:25 GMT

RE: Use of IPODs in Labs

SueKrueger — Fri, 05 Oct 2007 08:45:26 GMT

If it had not been for music I would have not made it

Whats wrong with just playing a radio for music?

Also, the earphones the bicyclist was wearing when I hit him WERE the cause of the accident - he said so himself!

Its not just a matter of not being able to hear whats going on, but as I've said before, I think listening through earphones causes you to be more absorbed in the music (rather than your surroundings) than if you were just listening to a radio in the background.

RE: Use of IPODs in Labs

Victor — Thu, 04 Oct 2007 19:36:18 GMT

Wow. I am clearly baffled and surprised that someone would clearly state that wearing earphones connected to an iPod is NOT a safety issue. California Vehicle Code Division 12, Chapter 5, Article 3.5, Section 37400 clearly makes it a vehicular infraction to be caught wearing ear phones while driving! This ensures that the person driving the vehicle can HEAR a blaring siren. That is, if you could not see the flashing lights. It does clearly state that earplugs must cover both ears. There is no problem as long as one ear is left uncovered. I could probably look up OSHA regulations as well and probably find the same thing.

RE: Use of IPODs in Labs

MR_HOLMES — Thu, 04 Oct 2007 19:00:36 GMT

I am not convinced that the ipod had anything to do with the accident. The same things could easily happen to any untrained worker or irresponsible cyclist.

I really want to understand this issue out of respect for my fellow coworkers. I could understand the possibility of the wires being caught in a centrifuge or something with moving parts but I think some people want to stop people from exercising a little personal freedom in the work place because they are unhappy. I worked the grave yard shift at a lab and received more than 500 samples each night that needed to be logged and bar coded for analysis. This was the most boring job in the world. If it had not been for music I would have not made it.

I think it depends on the work your doing and there should not be one blanket policy. It should be task specific and address any real safety issue.

RE: Use of IPODs in Labs

SueKrueger — Thu, 04 Oct 2007 12:07:17 GMT

I think the iPod is definately a safety issue - people using them cannot hear what's going on, and unlike a deaf person, are distracted and absorbed into the music, or whatever they're playing. I hit a bicyclist who was listening to an iPod while riding. He was unable to hear my car horn (or my car). He came off the right shoulder of the road, and literally summersaulted across the hood of my car. Luckily he wasn't hurt, and he admitted he never heard the horn.

RE: Use of IPODs in Labs

MR_HOLMES — Wed, 03 Oct 2007 19:00:08 GMT

I think IPODS are very bad. Sincerely Bill Gates.

I think it is much worse to have a chatty coworker blabbing in my ear than listening to my ipod. Some people have way to much time on their hands when you start worrying about music at work.

Ear buds provide an NR rating of less than 5, thus they do not reduce sound. I don't understand completely the safety issue. It has been my experience that people claim it is a safety issue because it is the easiest argument to make. I don't think having good hearing is a necessity for good lab practices or safety. I have worked people who are deaf in the lab. Never had any problems with burned fingers from autoclave trays or burning acid.

If an employee gets burned because they touch an autoclave, you need to train the employee not to touch things without verifying that they are cool, or you need to keep your hot stuff in a secure area until it cools. The only safety issue your lab has is inadequate training and procedures. The ipod probably has little to do with loss time accidents or injuring claims.

RE: Use of IPODs in Labs

Dedalus — Wed, 03 Oct 2007 10:33:53 GMT

John is, of course, correct. Safety is the primary thing. Here's a terrible scenario: you're running some kind of tricky acid digestion, you tell someone to 'look out.' But, they're wearing their "deaf hat" and they can't be bothered, so they vaguely nod at you...without really hearing you. And, something bad happens, and they wind up hurt.

RE: Use of IPODs in Labs

John Sansalone — Tue, 02 Oct 2007 14:14:19 GMT

On a general social level, I would tend to agree with Dedalus, but the issue at hand isn't really rudness, but safety. The reason that I think an IPOD is less safe is because the use of the ear buds not only provides the music (or whatever else the individual is listening to), but also acts as an earphone that prevents them from hearing other things - such as critical warnings.

The same might be true to some extent with a conventional pocket transistor radio, with an earpiece. A radio in an open room is background noise, which obviously has to be low enough for people to talk over. An IPOD acts like a much louder radio, where they may not hear that buzzer, shout, or whatever. I know that I've walked down the street, and could hear what people were listening to, from three or four feet away. I doubt they hear anything else, and it is no wonder they become oblivious. Scary related development: I've noticed is people driving, while listening to these things. It's probably impossible for the to hear sirens from emergency vehicles, which is a whole other story.