What Are U.S. Standards and Regulations for Asbestos Levels?

  • Learning Objectives
  • Introduction
  • Occupational Standards
  • Environmental Standards
  • Progress Check

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Upon completion of this section, you will be able to

  • Explain the Occupational Safety and Health Administration (OSHA) permissible exposure limit for asbestos and
  • Explain the U.S. Environmental Protection Agency’s (EPA) maximum contaminant level for asbestos in drinking water.

The earliest evidence of asbestos-associated disease in workers was found in the 1930s by British studies [Lee and Selikoff 1979]. We now know that the toxic effects of asbestos depend on the nature and extent of exposure, particularly on the:

  • Concentration of asbestos fibers involved in the exposure,
  • Duration of exposure,
  • Frequency of exposure,
  • Type of asbestos fibers involved in the exposure, and
  • Dimensions and durability of the asbestos fibers.

The Center for Disease Control and Prevention/National Institute for Occupational Safety and Health (NIOSH) and OSHA began establishing standards for asbestos in the 1970s. U.S. regulatory agencies such as EPA and OSHA recognize six asbestos and asbestiform minerals, i.e.,

  • Actinolite asbestos,
  • Amosite asbestos,
  • Anthophyllite asbestos,
  • Chrysotile asbestos,
  • Crocidolite, and
  • Tremolite asbestos

as legally regulated forms of asbestos out of the group of asbestiform minerals.

Asbestiform minerals are defined as crystal aggregates displaying these characteristics: groups of separable, long, thin, strong, and flexible fibers arranged in parallel [ATSDR 2001a].

Currently there is discussion underway to include asbestiform minerals that may have similar health effects to the previously mentioned forms of asbestos as regulated substances. However, nothing has been finalized at this time [OSHA 1992; NIOSH 2011a].

Currently, there are standards for asbestos in

  • Drinking water,
  • Some consumer products, and
  • Workplace air.

In 1986, OSHA in Standard 29 CFR 1910.1001 established the current permissible exposure limit (PEL) for asbestos in the workplace: (0.1 fibers/cc of air as a time weighed average) [OSHA 2012]. PELs are allowable exposure levels in workplace air averaged over an 8-hour shift of a 40 hour workweek. There are also OSHA standards (29 CFR 1915.1001) for shipyards and construction (1926.1101).

Additionally, OSHA standards (1915.1001 and 1926.1101) requires employers of all workers whose work exposes them to asbestos above the PEL or excursion limit (1.0 f/cc over 30-minute period) to

  • Provide training in the engineering controls, work practices, and proper use of personal protective equipment (PPE),
  • Train workers in safety before beginning work and annually,
  • Train workers regarding the health effects of asbestos exposure, and
  • Inform workers of the relationship between smoking, asbestos exposure and increased risk of lung cancer.

In addition, OSHA requires employers of workers who are exposed to asbestos above the PEL and who are employed in certain asbestos industries to

  • Provide and make sure of correct use of PPE (respirators, protective clothing like coveralls and goggles),
  • To undergo medical surveillance in order to identify those with signs of asbestos-associated disease, remove them from further exposure,
  • Comply with regulations requiring documentation for work-related injury claims, and
  • Provide information to workers about where they can go for help to stop smoking.

Components of the required medical surveillance include

  • Chest radiograph,
  • Physical examination,
  • Spirometric test, and
  • Standard questionnaire.

Further information about OSHA requirements is available at http://www.osha.gov/SLTC/asbestos/standards.html .

For further information about protection guidelines, contact NIOSH via 1-800-CDC-INFO or via http://www.cdc.gov/niosh/contact/ .

ATSDR does not consider the use of OSHA’s PEL for workplace exposures to be appropriate for environmentally exposed populations since residential and/or environmental exposures are 24 hours a day year round, much longer than the typical 8-hour day and 40-hour workweek exposures of workers. Children and the elderly, who are not typically exposed in the workplace, may be more susceptible to exposure.

EPA has established a maximum contaminant level (MCL) for asbestos in drinking water of 7 MFL (million fibers per liter > 10 µm in length) in drinking water [EPA 2011]. Asbestos in drinking water comes from two main sources:

  • Decay of water mains constructed of asbestos-containing cement, and
  • Erosions of naturally occurring asbestos deposits into watersheds [EPA 2012a].

In addition, EPA has

  • Banned spraying of asbestos in building interiors (for fireproofing and ceilings),
  • Developed guidelines for proper treatment of in-place asbestos in old buildings,
  • Recommended “no visible emissions” of asbestos,
  • Regulated demolition of buildings with asbestos (NESHAP rules), and
  • Regulated uses of asbestos in industrial products and construction.

More information on EPA rules and regulations regarding asbestos is available at http://www2.epa.gov/asbestos/asbestos-laws-and-regulations

The Asbestos Hazard Emergency Response Act of 1982 (CFR 40, Part 763, Subpart E) requires that local education agencies

  • Inspect schools for asbestos-containing material using certified inspectors,
  • Analyze these materials for asbestos content,
  • Post results and notify parents and employees if asbestos is found,
  • Test air levels following clean-up,
  • Develop appropriate management plans,
  • Communicate openly about any asbestos abatement needed, and
  • Maintain appropriate records [EPA 2012c].

EPA also warned school authorities that power buffing and power stripping of asbestos-tile floors in schools produces significant airborne asbestos levels. Floor maintenance must be performed by hand to prevent release of asbestos fibers.

  • OSHA’s PEL for asbestos in the workplace is 0.1 fibers/cc of air (8-hour TWA).
  • OSHA requires all asbestos-exposed workers to be trained in PPE; they must undergo medical surveillance if exposed above the PEL.
  • EPA’s MCL for asbestos in drinking water is 7 MFL greater than 10um in length (million fibers per liter) of drinking water.
  • Local education agencies must inspect schools and analyze friable material for asbestos content, communicate results, and maintain records.
  • Case Studies in Environmental Medicine
  • Grand Rounds in Environmental Medicine
  • Pediatric Environmental Health Training
  • Patient Education
  • Community Education

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Industrial Hygiene in Construction

Entries tagged with “ excursion limit ”..

Fri 12 Oct 2012

Air Monitoring – Multiple samples throughout the day

Posted by admin under ACGIH , Air Monitoring , Chemical Exposure , Exposure , industrial hygienist , Management , PEL (Perm Exp Limit) , TWA Comments Off on Air Monitoring – Multiple samples throughout the day

When measuring by air sampling for a job task, or an employee’s personal exposure, how many samples should you take?

Sometimes it is easier to place one filter cassette (or media) on the employee for the duration of their day.  At the end of the shift, you collect your equipment, mail it to the lab, and they spit out a 8-hour time weighted average (8-hour TWA). This is simple and easy to understand.

However, if you have the time and resources, it is usually beneficial to obtain multiple samples throughout the day. Taking multiple samples allow you to:

  • obtain peaks, lows, and anomalies.
  • look at: set up & clean up activities (separate from daily tasks)
  • measure multiple employees doing the same task (to better capture the job task)
  • calculate your own time weighted average
  • capture short term exposure levels (STELs), or excursion limits *
  • choose appropriate PPE for short duration tasks
  • determine if employees are “falsifying” the data (skewing the data high or low)
  • reduce filter overloading (in some cases)

There are some reasons NOT to obtain multiple samples:

  • collection limit constraints (sometimes the method of sampling does not allow for this type of multiple sampling)
  • it can be costly
  • it is very time consuming (and nearly impossible, if you have multiple pumps on multiple employees throughout the site)
  • difficulty interpreting the data (the math, the inferences, etc)

If you are hiring an industrial hygienist to perform air monitoring, ask about multiple samples. It might be slightly more expensive, but the information and data might be worth the cost.

* ACGIH recommends that if the compound does not have a STEL, all airborne levels should not exceed 3x the 8-hour TWA as an excursion limit.

Tags: air monitoring , excursion limit , exposure assessment , industrial hygiene , safety , sampling , STEL

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EXCURSION LIMIT Definition & Legal Meaning

Definition & citations:.

Specified, time-bound (typically 30 minutes), restricted exposure allowed to something unhealthy, even deadly. Meaningful especially in health and safety regulations.

This article contains general legal information but does not constitute professional legal advice for your particular situation. The Law Dictionary is not a law firm, and this page does not create an attorney-client or legal adviser relationship. If you have specific questions, please consult a qualified attorney licensed in your jurisdiction.

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Exploring Exposure Limits: What do those numbers mean?

what is excursion limit

If you’ve ever attended safety training, you surely have heard the terms PEL, TLV, REL and STEL.  Do these letters really have a meaning or are they just a bunch of alphabet soup?  These acronyms all represent different occupational exposure limits (OELs) that are derived by different organizations. An OEL is representative of the highest concentration a healthy worker can be exposed to for a full work week over the duration of their working life without experiencing an adverse effect.  Although similar, they each have a different goal and meaning.

Permissible Exposure Limit (PEL)

The Permissible Exposure Limit, or PEL, is the most widely known exposure limit.  This is the OSHA 8-hour time weighted average (TWA) exposure limit and is the only limit directly enforceable by regulation.  OSHA limits must be approved by Congress and take into account both health benefits and industry costs.  PELs are difficult to change because of the congressional approval required.  These limits apply to the general working population and are not meant to be applied to other, possibly more sensitive, populations.

Threshold Limit Value (TLV)

The Threshold Limit Value, or TLV, is set by ACGIH.  These 8-hour TWA limits are more representative of recent information and are outlined in the TLV guidebook, which is published annually.  Since they are consensus standards, they are not directly enforceable.  In addition, they are often stricter than the published PEL for the same chemical.   ACGIH does not consider financial impact when deriving TLVs, only health impact.

Recommended Exposure Limit (REL)

A Recommended Exposure Limit, or REL, is based on research done at NIOSH.  A REL is most commonly a 10-hour TWA (although some do exist as 8-hour limits).  NIOSH is the CDC funded research complement to OSHA, however the REL is also not directly enforceable and is considered a consensus standard as well.  The main goal of an REL is to recommend what an updated PEL should be to OSHA.

Short Term Exposure Limit (STEL)

The STEL is very similar to the other limits, however it is based on a 15-minute exposure, as opposed to a full working shift.  This is done to prevent employers from exposing employees to very high levels of an agent for short periods of time.  All agencies adopt STELs for some chemicals.

Now that you have all the OELs to consider in evaluating workplace exposure, how do you use that information?  Especially if they are all different, how do you move forward?  The best answer is to follow the most strict limit.  This always ensures the highest level of employee protection.  In addition, OSHA published the annotated Z table (Table-Z1) as a means of recognizing the advancement of OEL development since the 1970’s, which is when most PELs were published.  To circumvent the need to gain legislative approval, the annotated Z table which compares the OSHA exposure limits to that of NIOSH, ACGIH and Cal OSHA, was added to the OSHA website.  This means that OSHA can now use the general duty clause to enforce these exposure limits as well.

Occupational exposure limits can be confusing, especially when there are so many OELs established for the same chemical.  However, with a little insight into the origin of each limit, you can choose the best protective measures for your employee’s health.

This is the third blog in a ten-part Industrial Hygiene series that we are featuring monthly. We welcome your input on the series! To provide feedback, or for questions about industrial hygiene and for information on how input from a Certified Industrial Hygienist can benefit your safety program, please email [email protected] .

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A Legal Dictionary

Black’s Law Online Dictionary

what is excursion limit

What is EXCURSION LIMIT

Specified, time-bound (typically 30 minutes), restricted exposure allowed to something unhealthy, even deadly. Meaningful especially in health and safety regulations.

what is excursion limit

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Label Abbreviations & Descriptions

Chemical identification.

Name: The substances are primarily listed by the chemical name as it appears in the OSHA PELs, 29 CFR 1910.1000, TABLES Z-1, Z-2, Z-3; the ACGIH TLVs; or by common name.

CAS #: CAS numbers, Chemical Abstracts Service (CAS) Registry Number.

Physical Properties

NFPA 704: National Fire Protection Association’s Standard System for the Identification of the Hazards of Materials for Emergency Response. The standard presents a simple, readily recognized, and easily understood system of markings (commonly referred to as the “NFPA hazard diamond”) that provides an immediate general sense of the hazards of a material and the severity of these hazards as they relate to emergency response.

Monitoring Methods used by OSHA

Sampling method for OSHA compliance.

SLTC: Salt Lake Technical Center, OSHA. Sandy, UT 84070.

IMIS, IMIS code no.: The substance code currently assigned by OSHA to each substance in the integrated management system. IMIS Codes are reported on pre-printed OSHA-91B forms.

The following method status classifications have been assigned to OSHA methods. NIOSH method classification is taken from the method evaluation status published in their methods.

Note special instructions on sampling or obtaining sampling media from the SLTC. These instructions pertain to OSHA and 18(b) or 7(c)(1) state programs.

Analytical method instruments: Describesthe type of analysis performed at the SLTC. The following abbreviations are used:

On-Site Sampling Techniques/Methods

Detector tubes, chip measurement systems and direct reading instrument information has not been reviewed, except as noted.

Colorimetric detector tubes and Dräger Chip Measurement Systems (CMS) are used for screening to determine whether additional sampling is needed. If these readings exceed ½ the PEL, CSHOs should conduct additional sampling.

NOTE: OSHA has evaluated detector tubes for internal use; however, the number and type of tubes is limited. OSHA evaluates detector tubes primarily to select tubes for OSHA use. OSHA does not certify detector tubes, nor endorse products of any manufacturer. Omission of other manufacturers tubes does not mean the tubes have been found unsatisfactory.

Method References

  • NIOSH Manual of Analytical Methods (NMAM®), 4th Ed., U.S. Department of Health and Human Services (DHHS), National Institute for Occupational Safety and Health (NIOSH) Publication no. 94-113 (August, 1994); 1st Supplement, DHHS (NIOSH) Publication no. 96-135; 2nd Supplement, DHHS (NIOSH) Publication no. 98-119; and 3rdSupplement, DHHS (NIOSH) Publication no. 2003-154; Schlecht, P.C. and O'Connor, P.F., ([email protected]) Eds. Also, NIOSH Manual of Analytical Methods, 2nd Ed., Volume 1-7, Taylor, D.G., Ed. DHHS (NIOSH), Cincinnati, Ohio. Current NIOSH methods are available online.
  • OSHA Manual of Analytical Methods , USDOL, OSHA Salt Lake Technical Center (SLTC), 8660 South Sandy Parkway, Sandy, UT 84070-6406. Sampling and Analytical Methods are available at this website.
  • McLean, J.D. and Holland, J.F.: Development of a Portable Polarograph for Determination of Aldehydes in Automotive Exhaust and Production Plant Samples. Environmental Science and Technology, Vol. 9, pp. 127-131, (1975).
  • Mattocks, A.R.: Spectrophotometric Determination of Pyrazoline and Some Acrylic Amides and Esters. Anal. Chem., Vol. 40, pp. 1347, (1968).
  • Analysis of Pesticide Residues in Human and Environmental Samples. Environmental Protection Agency (EPA), Pesticide and Toxic Substances Effects Laboratory, Research Triangle Park, N.C., (1974).
  • Orion Electrode Instruction Manual. Orion Research, Inc., Cambridge, Mass., (1971).
  • Thomsen, E. and Stern, R.M.: A Simple Analytical Technique for the Determination of Hexavalent Chromium in Welding Fumes and other Complex Materials. The Danish Welding Institute Report No. 79-01, Scand. J. Work. Environ. & Health, Vol. 5, pp. 386-403, (1979).
  • The Industrial Environment--Its Evaluation and Control. U.S. Department of Health and Human Services (DHHS), National Institute for Occupational Safety and Health (NIOSH), Washington, D.C., (1973).
  • Brief, R.S., Venable, F.L.S., and Ajemian, R.S.: Nickel Carbonyl: Its Detection and Potential for Formation. Amer. Ind. Hyg. Assn. J., Vol. 26, pp. 72-76, (1965).
  • King, J.R., Nony, C.R., and Boeman, M.C.: Trace Analysis Diethylstilbestrol (DES) in Animal Chow by Parallel High-Speed Liquid Chromatography, Electron-Capture Gas Chromatography, and Radioassays. J. Chromatographic Science, Vol. 15, pp. 14, (1977).
  • OSHA Technical Manual (OTM), OSHA Instruction CPL 2-2.20B, USDOL OSHA Directorate of Technical Support, Washington, D.C. (1990). Current OSHA Technical Manual (OTM) (TED 01-00-015 [TED 1-0.15A]) is available at this website.
  • Occupational Exposure Sampling Strategy Manual (77-173), U.S. Department of Health and Human Services (DHHS), National Institute for Occupational Safety and Health (NIOSH), Cincinnati, Ohio, (1977).
  • Brief, R.S., Ajemian, R.S., and Confer, R.G.: Iron Pentacarbonyl: Its Toxicity, Detection, and Potential for Formation. Amer. Ind. Hyg. Assn. J., Vol. 28, pp. 21-30, (1967).
  • U.S. Code of Federal Regulations (CFR), Title 29, Part 1910, U.S. Government Printing Office, Washington, D.C.
  • Eller, P.E.: Determination of Nickel Carbonyl by charcoal tube collection and furnace atomic absorption spectrophotometry. Appl. Ind. Hyg. (1)3, pp 115-118, (1986, Sept).
  • Follow Manufacturer's Instruction Sheet. The Salt Lake Technical Center has not evaluated this product.

Exposure Limits

OSHA General Industry PEL:  OSHA Permissible Exposure Limit (PEL) for the General Industry - Action Level, Excursion Limit (EL), 8-Hour Time Weighted Average (TWA), Short Term Exposure Limit (STEL), Ceiling, or Stayed. Includes all changes to 29 CFR 1910.1000 to end published in the Federal Register.

OSHA Construction Industry PEL:  OSHA Permissible Exposure Limit (PEL) for the Construction Industry - Action Level, Excursion Limit (EL), 8-Hour Time Weighted Average (TWA), Short Term Exposure Limit (STEL), Ceiling, or Stayed. Includes all changes to 29 CFR 1926.1100 to end published in the Federal Register.

OSHA Maritime Industry PEL: OSHA Permissible Exposure Limit (PEL) for the Maritime Industry - Action Level, Excursion Limit (EL), 8-Hour Time Weighted Average (TWA), Short Term Exposure Limit (STEL), Ceiling, or Stayed. Includes all changes to 29 CFR 1915.1000 to end published in the Federal Register.

ACGIH TLV: American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV). Includes Biological Exposure Indices (BEIs), Sensitization, and Skin notations. For current information, references, and footnotes, see the yearly printed ACGIH TLV® and BEIs® Booklet.

NIOSH REL: National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Limit (REL).

Cal/OSHA: State of California, Divison of Occupational Safety and Health, Table AC-1 Permissible exposure limits for chemical contaminants.

Health Effects Code(s): Principal effect(s) of exposure to each substance, listed by OSHA Health Code and Health Effects. Health codes are used in determining if a violation of an air contaminant standard is serious or other-than- serious, based on guidelines in the Field Operations Manual, OSHA Instruction CPL 2.45B, chapter IV.

Carcinogenic Classifications:

NTP , carcinogenic classification as listed in or prior to the National Toxicology Program's (NTP) Report on Carcinogens (RoC). Search  NTP  for updated information.

Known To Be Human Carcinogens (also known as HUMAN CARCINOGEN):

There is sufficient evidence of carcinogenicity from studies in humans*, which indicates a causal relationship between exposure to the agent, substance, or mixture, and human cancer.

Reasonably Anticipated to be Human Carcinogens (also known as SUSPECT HUMAN CARCINOGEN): There is limited evidence of carcinogenicity from studies in humans*, which indicates that causal interpretation is credible, but that alternative explanations, such as chance, bias, or confounding factors, could not adequately be excluded,

there is sufficient evidence of carcinogenicity from studies in experimental animals, which indicates there is an increased incidence of malignant and/or a combination of malignant and benign tumors (1) in multiple species or at multiple tissue sites, or (2) by multiple routes of exposure, or (3) to an unusual degree with regard to incidence, site, or type of tumor, or age at onset,

there is less than sufficient evidence of carcinogenicity in humans or laboratory animals; however, the agent, substance, or mixture belongs to a well-defined, structurally related class of substances whose members are listed in a previous Report on Carcinogens as either known to be a human carcinogen or reasonably anticipated to be a human carcinogen, or there is convincing relevant information that the agent acts through mechanisms indicating it would likely cause cancer in humans.

*This evidence can include traditional cancer epidemiology studies, data from clinical studies, and/or data derived from the study of tissues or cells from humans exposed to the substance in question that can be useful for evaluating whether a relevant cancer mechanism is operating in people.

IARC , carcinogenic classification as indicated by International Agency for Research on Cancer (IARC), IARC Monographs on the Evaluation of the Carcinogenic Risk to Humans. Data includes chemicals covered through Volume 88.

Group 1:  The agent (mixture) is  carcinogenic to humans .

The exposure circumstance entails exposures that are carcinogenic to humans.

Group 2A:  The agent (mixture) is  probably carcinogenic to humans .

The exposure circumstance entails exposures that are probably carcinogenic to humans.

Group 2B:  The agent (mixture) is  possibly carcinogenic to humans .

The exposure circumstance entails exposures that are possibly carcinogenic to humans.

Group 3:  The agent (mixture or exposure circumstance) is  not classifiable as to its carcinogenicity to humans .

Group 4:  The agent (mixture) is  probably not carcinogenic to humans .

AIHA Emergency Response Planning Guidelines - ERPG-1/ERPG-2/ERPG-3:

ERPGs are air concentration guidelines for single exposures to agents and are intended for use as tools to assess the adequacy of accident prevention and emergency response plans, including transportation emergency planning, community emergency response plans and incident prevention and mitigation.

For further information or most current values, please see the

Additional Resources and Literature References

NOAA: CAMEO Chemicals Database of Hazardous Materials.

NIOSH: NIOSH Pocket Guide.

Literature References

Code of Federal Regulations (CFR) Title 29 Part 1910, USDOL, OSHA, Washington, D.C. Also available U.S. Government Printing Office, Washington, D.C.

Hawley's Condensed Chemical Dictionary, Fourteenth Edition, Van Nostrand Co., New York, 2001.

IARC Monographs on the Evaluation of Carcinogenic Risks to Humans . International Agency for Research on Cancer (IARC), Lyon, France. (90+ volumes). Available WHO Publications Centre USA, 49 Sheridan Ave., Albany, N.Y. 12210.

The Merck Index, Fourteenth Edition, Merck & Co., Rahway, N.J., 2006.

NIOSH Registry of Toxic Effects, U.S. Department of Health and Human Services (DHHS), National Institute for Occupational Safety and Health (NIOSH), Cincinnati, OH. Available U.S. Government Printing Office, Washington, D.C.

NIOSH Pocket Guide to Chemical Hazards , U.S. Department of Health and Human Services (DHHS), National Institute for Occupational Safety and Health (NIOSH), Cincinnati, OH. September, 2005, DHHS (NIOSH) 2005-149. Available U.S. Government Printing Office, Washington, D.C.

NIOSH/OSHA Health Guidelines, U.S. Department of Health and Human Services (DHHS), National Institute for Occupational Safety and Health (NIOSH), Washington, D.C., January, 1981, DHHS (NIOSH) No. 81-123. Available U.S. Government Printing Office, Washington, D.C. Current listing of NIOSH Health Guidelines .

Report on Carcinogens (RoC) . U.S. Department of Health and Human Services (DHHS), National Toxicology Program (NTP), (latest edition), Washington, D.C.

Toxic Substances Control Act Inventory, Environmental Protection Agency (EPA), Washington, D.C. Additional information is available online from EPA.

Pohanish, Richard P.: Sittig’s Handbook of Toxic and Hazardous Chemicals and Carcinogens, 6th Ed. , Elsevier, William Andrew Publishing, 2012.

Cohrssen, B., Bingham E. (eds.): Patty's Toxicology , 6 th Ed., New York: John Wiley & Sons, Inc., 2012.

Wexler, Philip. Encyclopedia of Toxicology , 3rd ed. New York: Elsevier, Academic Press, 2014.

A newsletter briefing on the intersection of technology and politics.

Four takeaways from the Supreme Court’s landmark social media arguments

what is excursion limit

Happy Tuesday! Justice Samuel Alito asked on Monday how much YouTube would weigh if it were a newspaper. Send your best guess to this ole' newspaper at: [email protected] . Below: A group of developers protest Apple’s blocking of web apps in Europe. First:

The Supreme Court on Monday weighed the fate of two landmark social media cases that could have massive implications for the future of the internet and speech online, as we reported .

The court heard oral arguments over a pair of state laws in Texas and Florida that would prohibit tech companies from removing certain content, which were passed in response to Republican allegations that digital platforms are stifling conservative viewpoints.

During roughly four hours of arguments, most justices seemed broadly skeptical that state governments have the power to set rules “for how social media platforms curate content” as my colleagues Ann E. Marimow and Cat Zakrzewski wrote .

They also offered hints about how they may handle the blockbuster cases.

Here are our four takeaways from the sessions: 

Justices call state laws overly ‘broad’

At various points, the justices criticized the broad scope of the Texas and Florida laws and the wide array of companies and services that they could cover. 

Justice Sonia Sotomayor early on lamented that the Florida law was “so unspecific” and “so, so broad, it’s covering almost everything.” She added that the internet’s “variety” is “infinite” and questioned whether the burden should be on the state to clarify its scope. 

Justice Amy Coney Barrett expressed similar concern, saying Florida’s law was “very broad” to the point that in addition to covering “traditional” social media platforms, it could also cover ride-hailing apps like Uber, Google’s search engine and Amazon’s e-commerce site.

Sotomayor said the same of the Texas law, warning that “laws like this that are so broad” may “stifle speech just on their face.” The criticisms bode well for tech industry groups.

Justices float kicking cases back to lower courts

Several justices broached the possibility of kicking the cases back to lower courts, while either upholding or overturning temporary blocks against the laws in the meantime. 

Justice Samuel Alito kicked things off by suggesting the high court could “vacate and remand” a lower-court ruling striking down key provisions in Florida’s law, punting it back to them. 

That move could allow questions about which specific company moderation practices are being challenged to be “fleshed out,” Alito argued. He suggested this could be a way to tackle the fact that industry groups were filing a “facial challenge” — which argues that the law is unconstitutional on its face even before any enforcement, rather than in how it was applied in a specific instance. 

Sotomayor said she initially had the same inclination as Alito — to vacate and remand — but hinted she may be inclined instead to uphold the injunction while remanding it. 

Sotomayor said it was “clear” from the discussion that many potentially covered practices “are expressive” and that some likely covered companies shouldn’t be considered “common carriers.” The remarks signal that the court could send the decision back with instructions for lower courts to dig into those distinctions.

Conservative court tackles tech ‘censorship’ allegations

Republicans have long accused social media platforms of unfairly “censoring” conservative voices. Tech industry groups have often responded by noting that the First Amendment protects against the suppression of free speech by the government — not private companies. 

That back-and-forth got a major airing Monday as some conservative justices pushed back on the notion that the term could apply to platforms’ moderation practices.

Justice Brett M. Kavanaugh said at one point that Florida Solicitor General Henry Whitaker “left out what I understand to be three key words in the First Amendment” and its protection against speech suppression, namely, “by the government.” Chief Justice John G. Roberts Jr. later echoed the remarks, saying, “The First Amendment restricts what the government can do.”

But other conservative at-times eschewed the distinction, with Alito asking if the term “content moderation” is “anything more than a euphemism for censorship?” Justice Clarence Thomas separately remarked: “I don't know of any protected speech interests in censoring other speech.” The comments suggest justices may not be aligned in their views on the matter.

Justices, states debate where to draw lines on the internet

The justices discussed ways to potentially distinguish between protected “speech” and business “conduct” by the tech companies that could be subject to the laws. However, it was not clear whether there’s consensus on the matter — or if it's an issue they’ll directly take up.

Justice Elena Kagan at one point asked whether a law could prohibit viewpoint discrimination in instances where you did not have to factor in questions about companies’ rights to “editorial discretion,” citing Venmo, Uber, Dropbox and Gmail as examples. 

“When you're running Venmo, you're not engaged in speech activities,” she said, suggesting the company’s activity is distinct from the likes of Facebook and YouTube, which curate news feeds. Paul Clement , the counsel representing tech trade groups NetChoice and CCIA, pushed back. “All of those things are still in the expressive business,” he said.

The justices also debated if and how the laws would apply to a business like e-commerce site Etsy. “Etsy is a supermarket that wants to sell only vintage clothes, and so it is going to, and does, limit users' content,” Kagan said. “They're going to have to censor.” 

Our top tabs

Developers protest apple's blocking of web apps in europe.

A group of open internet advocates and web developers are protesting Apple’s decision to stop allowing web apps in the European Union by writing an open letter to Apple CEO Tim Cook , my colleague Gerrit De Vynck reports for The Technology 202.

Unlike regular apps, which are downloaded through the App Store, web apps are essentially an icon linking out to a web page on the internet. They're easier to make and take up less space on devices. 

But Apple says it’s blocking them as part of its response to the EU's new laws regulating digital markets. 

The web developers say Apple's reasons are “at best unfounded.” It's just one part of a giant fight over the new law — called the Digital Markets Act — and how tech companies are responding to it.

Inside the industry

Facebook, YouTube to face new Canada ‘harmful’ content rules (Bloomberg)

Alphabet drops during renewed fears about Google’s AI offerings (Bloomberg)

Nvidia’s stunning ascent has also made it a giant target (Wall Street Journal)

Competition watch

Google steps up Microsoft criticism, warns of rival’s monopoly in cloud (Reuters)

Google Play judge calls $700 million settlement bad for customers (Bloomberg)

AT&T offers $5 credit to customers affected by service outage (New York Times)

Privacy monitor

New Biden order would stem flow of Americans’ sensitive data to China (By Ellen Nakashima and Drew Harwell)

Workforce report

Why Microsoft has accepted unions, unlike its rivals (New York Times)

Meet the Amazon ‘influencers’ making money off everything they own (By Caroline O'Donovan)

Kara Swisher once again punctures the puffed-up egos of Silicon Valley (By Will Oremus)

AI ‘dream girls’ are coming for porn stars’ jobs (By Tatum Hunter)

  • Bloomberg hosts an event , “Remedyfest,” featuring Sen. Elizabeth Warren (D-Mass.), FTC Chair Lina Khan and others, Tuesday at 9:15 a.m.
  • New American Online hosts an event , “The E.U. AI Act: Lessons for U.S. Policymakers,” Tuesday at 11 a.m.
  • Semafor hosts an event , “Mapping the Future of Digital Privacy,” Thursday at 9 a.m.
  • Punchbowl News hosts an event on AI policy with Sens. Mark R. Warner (D-Va.) and Todd Young (R-Ind.), Thursday at 9:30 a.m.
  • The FCC’s Space Bureau hosts open house event , “20 Years of Orbital Debris Mitigation,” Thursday at 10:30 a.m.

Before you log off

423,000 lbs https://t.co/HY81tzKv0Y pic.twitter.com/lFP6plbm01 — Kate Klonick (@Klonick) February 26, 2024

That ’ s all for today — thank you so much for joining us! Make sure to tell others to subscribe to  The Technology 202 here . Get in touch with Cristiano (via email or social media ) and Will (via email or social media ) for tips, feedback or greetings!

what is excursion limit

IMAGES

  1. PPT

    what is excursion limit

  2. EL Definición: Límite de excursión

    what is excursion limit

  3. What's a safe excursion limit (relative to Xmax)?

    what is excursion limit

  4. PPT

    what is excursion limit

  5. PPT

    what is excursion limit

  6. TWA, STEL, C, Excursion Limit

    what is excursion limit

VIDEO

  1. Calculus: Limits_2 Limit properties and examples of finding limits

  2. Limit State

  3. They Don't Want You To See This! This Will Change Everything

  4. Village excursion

  5. Limits Tricks

  6. AT&SF 2926 Goes to Tractor Brewing!

COMMENTS

  1. 1910.1001

    This section applies to all occupational exposures to asbestos in all industries covered by the Occupational Safety and Health Act, except as provided in paragraph (a) (2) and (3) of this section. 1910.1001 (a) (2) This section does not apply to construction work as defined in 29 CFR 1910.12 (b).

  2. TLV Chemical Substances Introduction

    Definition of the TLVs® Threshold Limit Values (TLVs ®) refer to airborne concentrations of chemical substances and represent conditions under which it is believed that nearly all workers may be repeatedly exposed, day after day, over a working lifetime, without adverse health effects.

  3. Excursion Limit Definition

    Excursion Limit (EL): The EL is an airborne concentration of asbestos to which no employee shall be exposed when not using respiratory protection.

  4. What Are U.S. Standards and Regulations for Asbestos Levels?

    Additionally, OSHA standards (1915.1001 and 1926.1101) requires employers of all workers whose work exposes them to asbestos above the PEL or excursion limit (1.0 f/cc over 30-minute period) to. Provide training in the engineering controls, work practices, and proper use of personal protective equipment (PPE),

  5. PDF INTRODUCTION TO THE CHEMICAL SUBSTANCES

    Definition of the TLVs® Threshold limit values (TLVsfi) refer to airborne concentrations of chemical substances and repre- sent conditions under which it is believed that nearly allworkers may be repeatedly exposed, day after day, over a working lifetime, without adverse health effects.

  6. Clarification of 29 CFR 1910.1047 (h) (2) Requirements for Emergency

    The EL is not interpreted as an emergency exposure limit, it is, instead, a PEL; the excursion limit is an allowable time-weighted average exposure under the standard as collected over a 15 minute sampling period.

  7. PDF FactSheet

    Permissible Exposure Limit (PEL) for asbestos is 0.1 fiber per cubic centimeter of air as an eight-hour time-weighted average (TWA), with an excursion limit (EL) of 1.0 asbestos fibers per cubic centimeter over a 30-minute period. The employer must ensure that no one is exposed above these limits.

  8. Permissible exposure limit

    The permissible exposure limit (PEL or OSHA PEL) is a legal limit in the United States for exposure of an employee to a chemical substance or physical agent such as high level noise. Permissible exposure limits were established by the Occupational Safety and Health Administration (OSHA). Most of OSHA's PELs were issued shortly after adoption of the Occupational Safety and Health (OSH) Act in 1970.

  9. Excursion Limit

    Related Code Sections 1910.1001 (c) (2) Toxic and Hazardous Substances, Excursion Limit The employer shall ensure that no employee is exposed to an airborne concentration of asbestos in excess of 1.0 fiber per cubic centimeter of air (1 f ...

  10. PDF © 2023 USPC

    MKT temperature excursion limits in Mean Kinetic Tem䕖큁erature in the Evaluation of Tem䕖큁erature Excursions During Storage and Trans䕖큂ortation of Drug_ Products (1079.2}_ are specific for products stored at controlled room temperature (20°-25°) and at controlled cool temperature (2°-8°).

  11. PDF Operations Manual Threshold Limit Values (Tlv ) for Chemical ...

    4 . THRESHOLD LIMIT VALUES (TLV®) FOR CHEMICAL SUBSTANCES COMMITTEE . Committee Mission The Threshold Limit Value for Chemical Substances (TLV®-CS) Committee is appointed by the Board of Directors of ACGIH® to develop occupational exposure guidelines for chemical substances. The issuance of Threshold Limit Values (TLVs®) and their supporting Documentation is the principal

  12. PDF Managing Environmental Monitoring Excursions

    When an excursion occurs (ie, the colony forming unit [CFU] limits are exceeded), the pharmacy must determine why it occurred and if it unfavorably affected the CSPs that were prepared during the time of the excursion.

  13. PDF OSHA Fact Sheet: Ethylene oxide

    Employee exposure may not exceed the short-term excursion limit of 5 ppm EtO averaged over any 15-minute sampling period. These limits are called permissible exposure limits (PELs). Most occupational exposures to EtO are covered by the OSHA standard.

  14. PDF SAFE OPERATING LIMITS / INTEGRITY OPERATING WINDOWS

    Assists in determining potential causes of the excursion and corrective ... Established limits for process variables (parameters) that can affect the integrity of the equipment if the process operation deviates from the established limits for a predetermined length of time (includes critical, standard and informational

  15. excursion limit

    capture short term exposure levels (STELs), or excursion limits * choose appropriate PPE for short duration tasks determine if employees are "falsifying" the data (skewing the data high or low) reduce filter overloading (in some cases) There are some reasons NOT to obtain multiple samples:

  16. EXCURSION LIMIT Definition & Meaning

    EXCURSION LIMIT Definition & Legal Meaning Definition & Citations: Specified, time-bound (typically 30 minutes), restricted exposure allowed to something unhealthy, even deadly. Meaningful especially in health and safety regulations.

  17. Exploring Exposure Limits: What do those numbers mean?

    The Permissible Exposure Limit, or PEL, is the most widely known exposure limit. This is the OSHA 8-hour time weighted average (TWA) exposure limit and is the only limit directly enforceable by regulation. OSHA limits must be approved by Congress and take into account both health benefits and industry costs. PELs are difficult to change because ...

  18. What is "Excursion"?

    If a speaker is pushed beyond its limits you may hear a "cracking" sound as the voice coil slams into the bottom of the magnetic gap (during inward movement) or slips out of the gap (during outward movement). This is called overexcursion or "bottoming out" and usually just precedes a failure. Glossary

  19. 1910.1001 App B

    1910 Part Number Title: Occupational Safety and Health Standards Subpart: 1910 Subpart Z Subpart Title: Toxic and Hazardous Substances Standard Number: 1910.1001 App B Title: Detailed Procedures for Asbestos Sampling and Analysis - Non-mandatory GPO Source: e-CFR

  20. PDF To the limit

    Ceiling limit: The maximum exposure limit, which cannot be exceeded for any length of time. A PEL may be calculated on average exposure throughout the day (TWA) or on the amount that's not safe for more than a short period of time (STEL). The ceiling limit is the amount that is never safe, for any period of time. Not all substances have a ...

  21. What is EXCURSION LIMIT? Definition of EXCURSION LIMIT (Black's Law

    What is EXCURSION LIMIT Specified, time-bound (typically 30 minutes), restricted exposure allowed to something unhealthy, even deadly. Meaningful especially in health and safety regulations. « EXCURSION FARE EXCURSIONIST »

  22. OSHA Occupational Chemical Database

    OSHA General Industry PEL: OSHA Permissible Exposure Limit (PEL) for the General Industry - Action Level, Excursion Limit (EL), 8-Hour Time Weighted Average (TWA), Short Term Exposure Limit (STEL), Ceiling, or Stayed. Includes all changes to 29 CFR 1910.1000 to end published in the Federal Register.

  23. Analysis

    "Etsy is a supermarket that wants to sell only vintage clothes, and so it is going to, and does, limit users' content," Kagan said. "They're going to have to censor."