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exposure limits construction site

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On construction sites, occupational exposure limits must be managed using the applicable OSHA permissible exposure limits (PELs), while also considering other occupational exposure limits such as NIOSH RELs and ACGIH TLVs for hazard evaluation. OSHA standards are the legally enforceable limits, and employers are legally required to meet the levels specified by an OSHA standard. Safety data sheets are also expected to list known exposure limits in Section 8, including OSHA PELs and ACGIH TLVs. [2] [2] [8]

  • TWA is the average airborne exposure over an 8-hour work shift.
  • STEL is a 15-minute time-weighted average that must not be exceeded during the workday.
  • Ceiling is a concentration that must not be exceeded during any part of the workday.
  • Skin notation means dermal absorption can contribute materially to total exposure and requires controls such as gloves, coveralls, goggles, engineering controls, or work practices.

[3] [3] [3] [3] For worker exposure monitoring, employers should use recognized sampling and analytical methods and compare results to the applicable limit type for each contaminant. Monitoring should be designed to characterize dusts, fumes, gases, vapors, and mists generated by construction tasks such as cutting, sanding, spraying, blasting, demolition, and adhesive or coating application. Where mixtures are present, equivalent exposure must be calculated; under Subpart Z mixture calculations, the summed ratio of each contaminant concentration to its limit must not exceed 1\.0\. [1] [5] [5]

Examples of air contaminant thresholds commonly relevant to construction:

  • Particulates not otherwise regulated: total particulate 10 mg/m³ TWA and 20 mg/m³ STEL; respirable fraction 5 mg/m³ TWA and 10 mg/m³ STEL.
  • Limestone dust: OSHA PEL 15 mg/m³ total dust TWA and 5 mg/m³ respirable fraction TWA.
  • Talc not containing asbestiform fibers: ACGIH TLV 2 mg/m³ respirable fraction; OSHA PEL Z3 TWA 2 mg/m³ in the cited product SDS.
  • Respirable crystalline silica: OSHA PEL 50 µg/m³ respirable dust TWA in current OSHA-listed SDS entries; older formula-based OSHA Z3 limits also appear in SDSs and legacy references.
  • Titanium dioxide: ACGIH TLV 2\.5 mg/m³ respirable fraction for fine-scale particles; OSHA PEL 15 mg/m³ total dust TWA.
  • Some vapors and aerosols also have STELs and TWAs; for example, 2-methylpentane-2,4-diol is listed with ACGIH STEL 10 mg/m³ inhalable aerosol, STEL 50 ppm vapor, and TWA 25 ppm vapor.

[7] [1] [4] [6] [10] [9] Respirable crystalline silica is one of the most important respiratory hazards on construction sites because it is generated during abrasive blasting, cutting, grinding, drilling, and similar dust-producing work. The cited materials show both modern and legacy silica limits. One source states that NIOSH recommends 0\.05 mg/m³ TWA for respirable crystalline silica, ACGIH lists 0\.1 mg/m³ in the historical reference cited there, and the OSHA construction PEL in that source is the formula 250 million particles per cubic foot divided by "% SiO2 \+ 5\." More recent SDSs also list OSHA's respirable crystalline silica PEL as 50 µg/m³ respirable dust TWA and ACGIH TLV as 0\.025 mg/m³ respirable fraction. Because silica is associated with silicosis and potential carcinogenicity, exposures should be driven as low as practicable, not merely kept just below the limit. [2] [2] [2] [6] [4]

OSHA compliance requires employers to control exposures primarily through feasible engineering and work-practice controls. Respirators are not the first-line control; they are used when engineering or administrative controls cannot fully achieve compliance, and then they must be used under a compliant respiratory protection program. For certain substance-specific standards such as lead in construction, respirator protection factors may only be used in exposure adjustment when the employer has complied with the required engineering/work-practice and respiratory protection provisions. [5] [5] [11]

  • Use process enclosures, local exhaust ventilation, wet methods where applicable, and task-specific dust suppression to keep airborne contaminants below statutory or recommended limits.
  • For spray, aerosol, solvent, or vapor-generating work, ensure adequate ventilation; where flammable vapors or explosive atmospheres may occur, use explosion-proof ventilation equipment.
  • Assess oxygen-deficient atmospheres as respiratory hazards; atmospheres below 19\.5% oxygen are hazardous and require appropriate respiratory protection and confined-space controls where applicable.
  • Use PPE for skin and eye exposure when contaminants have skin notation or splash/contact potential, but do not rely on PPE as the sole control when feasible engineering controls are available.

[4] [9] [12] [7] Construction safety compliance documentation should, at minimum, include: a current chemical inventory; the SDS for each hazardous product used on site; a written exposure assessment or industrial hygiene sampling records; objective data or air-monitoring results supporting exposure determinations; records showing how TWAs, STELs, ceilings, and mixture exposures were evaluated; documentation of engineering controls and maintenance; respirator hazard assessments, medical evaluations, fit testing, and training records where respirators are used; PPE hazard assessments; worker training records; and corrective actions taken when exposures approach or exceed limits. SDS Section 8 is especially important because it identifies known exposure limits and recommended controls, and OSHA may use SDSs, internal policies, consultant reports, illness logs, and industry guidance as evidence that a respiratory hazard was recognized. [8] [8] [1]

In practice, a compliant construction exposure-control program should identify the contaminant, determine the applicable OSHA limit, sample representative employee exposures, evaluate 8-hour TWA and any 15-minute STEL or ceiling requirements, account for mixture exposures where relevant, implement feasible engineering/work-practice controls first, and then use respiratory protection and other PPE as supplemental protection. For high-concern agents such as respirable crystalline silica and lead, employers should be especially conservative and maintain thorough documentation of exposure determinations and controls. [3] [5] [5]

12 source record(s)

Sources used for this answer

[1] Oregon OSHA Program Directive | Lead: Exposure In Construction

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# Inspection Guidance and Citation Policy (cont.) - the removal of lead-based paint and lead-contaminated dust, the perma- nent containment or encapsulation of lead-based paint, the replacement of lead-painted surfaces or fixtures, and the removal or covering of lead contaminated soil; and - all preparation, cleanup, disposal, and post abatement clearance testing activities associated with such measures. - INTERIM CONTROLS - The term 'interim controls' means a set of mea- sures designed to reduce temporarily human exposure or likely exposure to lead-based paint hazards, including specialized cleaning, repairs, mainten- ance, painting, temporary containment, ongoing monitoring of lead-based paint hazards or potential hazards and the establishment and operation of management and resident education programs. All such activities (with the exception of the establishment and operation of management and resident education programs) conducted as part of an employer's lead abatement program, or a lead operations and maintenance program that implements specific interim controls are covered by 1926.62. Regulation Inspection Guidance 1926.62(c) Permissible exposure limit (c)(3) The standard permits the use of respiratory protection and the adjustment of employee exposure based on the assigned protection factor of the respiratory protection to achieve compliance with the permissible exposure limit (PEL) only if the employer has complied with 1926.62(e)(1), Engineering and work practice controls and (f), Respiratory protection. (See Appendix B for guidance on exposure calculation for compliance with 1926.62 (c)(3).) - Citation Policy When the calculated time-weighted average (TWA) after taking into account the protection factor of the respirator still exceeds the PEL, a citation for violation of 1926.62(c)(1) or (c)(2) shall be issued. Section (c)(3) is explanatory in nature and shall not be cited. Note that the employer is also in violation of 1926.62(f)(2)(i) as well…

[2] LIQUID NAILS Paneling & Molding Interior Construction Adhesive (Low-VOC)

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# Section 7. Handling and storage (cont.) ## Control parameters (cont.) Product code 00407682 # Product name LN-710 PANELING VOC AHE71024TN0 Date of issue 3 May 2025 Version 18 # Section 8. Exposure controls/personal protection titanium dioxide OSHA PEL Z3 (United States, 6/2016) TWA 8 hours: 250 / (%SiO₂+5) mppcf. Form: Respirable. TWA 8 hours: 10 / (%SiO₂+2) mg/m3. Form: Respirable. ACGIH TLV (United States, 1/2024) TWA 8 hours: 2.5 mg/m3. Form: respirable fraction, finescale particles. OSHA PEL (United States, 5/2018) TWA 8 hours: 15 mg/m3. Form: Total dust. <table><tr><th colspan="4">Key to abbreviations</th></tr><tr><td>A</td><td>= Acceptable Maximum Peak</td><td>S</td><td>= Potential skin absorption</td></tr><tr><td>ACGIH</td><td>= American Conference of Governmental Industrial Hygienists.</td><td>SR</td><td>= Respiratory sensitization</td></tr><tr><td>C</td><td>= Ceiling Limit</td><td>SS</td><td>= Skin sensitization</td></tr><tr><td>F</td><td>= Fume</td><td>STEL</td><td>= Short term Exposure limit values</td></tr><tr><td>IPEL</td><td>= Internal Permissible Exposure Limit</td><td>TD</td><td>= Total dust</td></tr><tr><td>OSHA</td><td>= Occupational Safety and Health Administration.</td><td>TLV</td><td>= Threshold Limit Value</td></tr><tr><td>R</td><td>= Respirable</td><td>TWA</td><td>= Time Weighted Average</td></tr><tr><td>Z</td><td>= OSHA 29 CFR 1910.1200 Subpart Z - Toxic and Hazardous Substances</td><td></td><td></td></tr></table> ## Consult local authorities for acceptable exposure limits. Recommended monitoring procedures Reference should be made to appropriate monitoring standards. Reference to national guidance documents for methods for the determination of hazardous substances will also be required. : ## Appropriate engineering controls ## Environmental exposure controls ## Eye/face protection Skin protection Hand protection ## Individual protection measures Hygiene measures : If user operations generate dust, fumes, gas, vapor or m…

[3] OSHA Letter of Interpretation | Enforcement Policy for Respiratory Hazards Not Covered by OSHA Permissible Exposure Limits

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# Occupational Safety and Health Administration (cont.) - However, if the exposed employees were wearing appropriate respiratory protection with no deficiencies in the respirator program, then the likelihood that OSHA could establish a respiratory hazard covered by the general duty clause would be low. b. The hazard was recognized - OSHA can establish this element in one of two ways. (1) For employer recognition: Evidence may include employee complaints to management, illness and injury logs, consultant reports, a previous HAL, internal safety and health policies related to workplace operations involving the chemical that may refer to an OEL, or information from a manufacturer describing safety and health precautions for equipment or chemicals used in the workplace such as the chemical manufacturers' safety data sheet (SDS). (2) For industry recognition: Evidence may include an industry or trade association's guidance document, or an assessment from an industry expert describing the work practice or operation used at the establishment and explaining the particular health hazards and recommended control measures. Alternatively, a similar publication from a (non-OSHA) federal, state, or local government agency, or from a professional organization, may also provide good evidence. Some examples of government agencies include the National Institute for Occupational Safety and Health (NIOSH), the National Toxicology Program (NTP), and the U.S. Environmental Protection Agency (EPA). Examples of organizations include The Center for Construction Research and Training (CPWR, formerly The Center to Protect Workers' Rights), the American Conference of Governmental Industrial Hygienists (ACGIHTM), and the Occupational Alliance for Risk Science (OARS). c. The hazard was causing or was likely to cause death or serious physical harm - Although an illness or injury from the measured exposure need not have occurred yet, the strongest evidence is an employee illness/injury, hospit…

[4] LIQUID NAILS Tub Surround Advanced Interior Construction Adhesive

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# Product code 00428247 Date of issue 3 May [redacted street address]-1015 LIQUID NAILS TUB SURROUND INTERIOR/EXTERIOR ADVANCED CONSTRUCTION ADHESIVE (cont.) ## Section 8. Exposure controls/personal protection (cont.) Product code 00428247 Date of issue [redacted street address]-1015 LIQUID NAILS TUB SURROUND INTERIOR/EXTERIOR ADVANCED CONSTRUCTION ADHESIVE 8.02 ## Section 8. Exposure controls/personal protection <table><tr><th>Ingredient name</th><th>Exposure limits</th></tr><tr><td>Limestone proprietary trade secret organic amide wax trimethoxyvinylsilane N-(3-(trimethoxysilyl)propyl)ethylenediamine dibutylbis(pentane-2,4-dionato-O,O')tin</td><td>OSHA PEL (United States, 5/2018) TWA 8 hours: 15 mg/m3. Form: Total dust. TWA 8 hours: 5 mg/m3. Form: Respirable fraction. ACGIH TLV (United States) Absorbed through skin. TWA: 50 ppm. ACGIH TLV (United States) TWA: 10 mg/m3. Form: inhalable dust. TWA: 3 mg/m3. Form: Respirable dust. None. None. ACGIH TLV (United States) Absorbed through skin. STEL: 0.2 mg/m3. TWA: 0.1 mg/m3 (as Sn). OSHA PEL (United States) TWA: 0.1 mg/m3 (as Sn). Form: Total dust. TWA: 0.1 mg/m3 (as Sn).</td></tr></table> <table><tr><th colspan="4">Key to abbreviations</th></tr><tr><td>A</td><td>= Acceptable Maximum Peak</td><td>S</td><td>= Potential skin absorption</td></tr><tr><td>ACGIH</td><td>= American Conference of Governmental Industrial Hygienists.</td><td>SR</td><td>= Respiratory sensitization</td></tr><tr><td>C</td><td>= Ceiling Limit</td><td>SS</td><td>= Skin sensitization</td></tr><tr><td>F</td><td>= Fume</td><td>STEL</td><td>= Short term Exposure limit values</td></tr><tr><td>IPEL</td><td>= Internal Permissible Exposure Limit</td><td>TD</td><td>= Total dust</td></tr><tr><td>OSHA</td><td>= Occupational Safety and Health Administration.</td><td>TLV</td><td>= Threshold Limit Value</td></tr><tr><td>R</td><td>= Respirable</td><td>TWA</td><td>= Time Weighted Average</td></tr><tr><td>Z</td><td>= OSHA 29 CFR 1910.1200 Subpart Z - Toxic and…

[5] Construction Health Hazard Evaluation: Johnson Brothers Company Pittsburgh, Pennsylvania HETA 93-1037-2541

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# Page 8 - Health Hazard Evaluation Report No. 93-1037 The primary sources of environmental evaluation criteria for the workplace are: (1) NIOSH Criteria Documents and recommendations; (2) the American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Values (TLVS) (6); and (3) OSHA Occupational Health Standards. (7) OSHA standards take into account the feasibility of controlling exposures in the various industries where the agents are used. The NIOSH Recommended Exposure Limits (RELs), by contrast, are based primarily on concerns relating to the prevention of occupational disease. The employer is legally required to meet those levels specified by an OSHA standard. A time-weighted average (TWA) exposure refers to the average airborne concentration of a substance during a normal workday. Some substances have recommended short term exposure limits (STEL) or ceiling (C) values which are intended to supplement the TWA where there are recognized toxic effects from high short-term exposures. The environmental exposure criteria for some substances monitored during this investigation are shown in Table I. ## SILICA Because of the extremely high risk of silicosis associated with sandblasting, and the difficulty in controlling exposure to respirable silica during sandblasting operations, the use of crystalline silica for abrasive blasting cleaning operations was restricted in Great Britain in 1950, and in other European countries in 1966. In 1974, NIOSH recommended that silica sand (or other substances containing >1% free silica) be prohibited as an abrasive blasting material. (9) In addition to causing silicosis, evidence now indicates that crystalline silica is a potential occupational carcinogen. (1 (10,11,12) NIOSH recommends an exposure limit for respirable crystalline silica of 0.05 mg/m³, expressed as a TWA. The 1995-1996 ACGIH TLV for respirable crystalline silica (as quartz) is 0.1 mg/m³. For construction operations (including the Johnson …

[6] MNOSHA Permissible Exposure Limits

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# SUBPART Z -- TOXIC AND HAZARDOUS SUBSTANCES 1910.1000-AIR CONTAMINANTS An employee's exposure to any substance listed in Table Z-1-A of this section shall be limited in accordance with the requirements of the following paragraphs of this section. (a) Table Z-1-A. Limits for Air Contaminants (1) & (2) Enforcement of Transitional Limits has expired. See Paragraph (3) for Limits. (3) Limits for Air Contaminants Columns. An employee's exposure to any substance listed in Table Z-1-A shall not exceed the Time Weighted Average (TWA), Short Term Exposure Limit (STEL) and Ceiling Limit specified for that substance in Table Z-1-A. (4) Skin Designation. To prevent or reduce skin absorption, an employee's skin exposure to substances listed in Table Z-1-A with an "X" in the Skin Designation column following the substance name shall be prevented or reduced to the extent necessary in the circumstances through the use of gloves, coveralls, goggles, or other appropriate personal protective equipment, engineering controls or work practices. (5) Definitions. The following definitions are applicable to the Limits for Air Contaminants columns of Table Z- 1-A: (i) Time weighted average (TWA) is the employee's average airborne exposure in any 8-hour work shift of a 40-hour work week which shall not be exceeded. (ii) Short term exposure limit (STEL) is the employee's 15-minute time weighted average exposure which shall not be exceeded at any time during a work day unless another time limit is specified in a parenthetical notation below the limit. If another time period is specified, the time weighted average exposure over that time period shall not be exceeded at any time during the working day. (iii) Ceiling is the employee's exposure which shall not be exceeded during any part of the work day. If instantaneous monitoring is not feasible, then the ceiling shall be assessed as a 15-minute time weighted average exposure which shall not be exceeded at any time over a wor…

[7] HOMAX PRO GRADE Interior Aerosol Ceiling Texture Popcorn - Water Based

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# Product code 00384783 Date of issue 3 May 2025 Version 11 Product name 4175 PRO GRADE - AEROSOL CEILING TEXTURE WATER BASED - POPCORN - CANADA (cont.) ## Precautions for safe handling (cont.) Product code 00384783 Date of issue 3 May 2025 Version 11 Product name 4175 PRO GRADE - AEROSOL CEILING TEXTURE WATER BASED - POPCORN - CANADA # Section 8. Exposure controls/personal protection Control parameters Occupational exposure limits <table><tr><th>Ingredient name</th><th>Exposure limits</th></tr><tr><td>mestone dimethyl ether Talc, not containing asbestiform fibres 2-methylpentane-2,4-diol crystalline silica, respirable powder (&lt;10 microns)</td><td>OSHA PEL (United States, 5/2018) TWA 8 hours: 15 mg/m3. Form: Total dust. TWA 8 hours: 5 mg/m3. Form: Respirable fraction. None. ACGIH TLV (United States, 1/2024) TWA 8 hours: 2 mg/m3. Form: Respirable fraction. OSHA PEL Z3 (United States) TWA: 2 mg/m3. ACGIH TLV (United States, 1/2024) STEL 15 minutes: 10 mg/m3. Form: Inhalable fraction. Aerosol only.. STEL 15 minutes: 50 ppm. Form: Vapor fraction. TWA 8 hours: 25 ppm. Form: Vapor fraction. ACGIH TLV (United States, 1/2024) [Silica, crystalline] TWA 8 hours: 0.025 mg/m3. Form: Respirable fraction. OSHA PEL Z3 (United States, 6/2016) TWA 8 hours: 250 / (%SiO₂+5) mppcf. Form: Respirable. TWA 8 hours: 10 / (%SiO₂+2) mg/m3. Form: Respirable.</td></tr></table> <table><tr><th colspan="4">Key to abbreviations</th></tr><tr><td>A</td><td>= Acceptable Maximum Peak</td><td>S</td><td>= Potential skin absorption</td></tr><tr><td>ACGIH</td><td>= American Conference of Governmental Industrial Hygienists.</td><td>SR</td><td>= Respiratory sensitization</td></tr><tr><td>C</td><td>= Ceiling Limit</td><td>SS</td><td>= Skin sensitization</td></tr><tr><td>F</td><td>= Fume</td><td>STEL</td><td>= Short term Exposure limit values</td></tr><tr><td>IPEL</td><td>= Internal Permissible Exposure Limit</td><td>TD</td><td>= Total dust</td></tr><tr><td>OSHA</td><td>= Occupational Safety and …

[8] LIQUID NAILS Drywall Interior Construction Adhesive - Latex Based

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# Section 7. Handling and storage (cont.) ## Control parameters (cont.) Product code 00407729 Product name DWP-24 DRYWALL AHED2412TN0 Date of issue 4 May 2025 Version 19 # Section 8. Exposure controls/personal protection <table><tr><th>crystalline silica, respirable powder (&lt;10 microns) crystalline silica, non-respirable powder (&gt;10 microns)</th><th>TWA 8 hours: 0.025 mg/m3. Form: Respirable fraction. OSHA PEL (United States, 5/2018) [Silica, crystalline] TWA 8 hours: 50 µg/m³. Form: Respirable dust. OSHA PEL Z3 (United States, 6/2016) TWA 8 hours: 250 / 2 X (%SiO₂+5) mppcf. Form: Respirable. TWA 8 hours: 10 / (%SiO₂+2) mg/m3. Form: Respirable. TWA 8 hours: 30 / (%SiO₂+2) mg/m3. Form: Total dust. ACGIH TLV (United States, 1/2024) [Silica, crystalline] TWA 8 hours: 0.025 mg/m3. Form: Respirable fraction. OSHA PEL Z3 (United States, 6/2016) TWA 8 hours: 250 / (%SiO₂+5) mppcf. Form: Respirable. TWA 8 hours: 10 / (%SiO₂+2) mg/m3. Form: Respirable. ACGIH TLV (United States, 1/2024) [Silica, crystalline] TWA 8 hours: 0.025 mg/m3. Form: Respirable fraction. OSHA PEL (United States, 5/2018) [Silica, crystalline] TWA 8 hours: 50 µg/m³. Form: Respirable dust. OSHA PEL Z3 (United States, 6/2016) TWA 8 hours: 250 / (%SiO₂+5) mppcf. Form: Respirable. TWA 8 hours: 10 / (%SiO₂+2) mg/m3. Form: Respirable.</th></tr></table> <table><tr><th colspan="4">Key to abbreviations</th></tr><tr><td>A</td><td>= Acceptable Maximum Peak</td><td>S</td><td>= Potential skin absorption</td></tr><tr><td>ACGIH</td><td>= American Conference of Governmental Industrial Hygienists.</td><td>SR</td><td>= Respiratory sensitization</td></tr><tr><td>C</td><td>= Ceiling Limit</td><td>SS</td><td>= Skin sensitization</td></tr><tr><td>F</td><td>= Fume</td><td>STEL</td><td>= Short term Exposure limit values</td></tr><tr><td>IPEL</td><td>= Internal Permissible Exposure Limit</td><td>TD</td><td>= Total dust</td></tr><tr><td>OSHA</td><td>= Occupational Safety and Health Administration.</td><td>TLV</td><t…

[9] WAC 296-841-[redacted postal code] - Permissible exposure limits (PELs)

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# WAC 296-841-[redacted postal code] Permissible exposure limits (PELS). IMPORTANT: The following information applies to Table 3, Permissible Expo- sure Limits (PELS) for Airborne Contaminants. (1) Ppm refers to parts of vapor or gas per million parts of air by volume, at 25 degrees C and 760 mm Hg pressure. (2) Mg/m³ refers to milligrams of an airborne contaminant per cu- bic meter of air. (3) F/cc refers to fibers per cubic centimeter of air. (4) For a metal that is measured as the metal itself, only the CAS number for the metal is given. The CAS numbers for individual com- pounds of the metal are not provided. For more information about CAS registry numbers see the website: http://www.cas.org. (5) Short-term exposure limits (STEL) pertain to fifteen-minute exposure periods, unless another time period is noted in Table 3. (6) An "X" in the "skin" column indicates the contaminant can be absorbed through the skin, either by airborne or direct contact. (a) Personal protective equipment (PPE) to prevent skin contact may be needed to minimize the risk for adverse health effects when em- ployees are exposed to these chemicals. (b) Requirements for the use of gloves, coveralls, goggles, and other personal protective equipment can be found in WAC [redacted identifier], Personal protective equipment (PPE). (7) Nuisance dusts (also known as inert dusts) are included in the Table 3 listing, particulates not otherwise regulated (PNOR). - The PNOR listing in Table 3 also applies to other particulate airborne contaminants for which a specific PEL is NOT listed unless the airborne contaminant is found to require a lower limit. (8) The respirable fraction of a particulate airborne contaminant is measured by sampling with a size-selector having the following characteristics: <table><tr><th>Mean aerodynamic diameter in micrometers</th><th>Percent passing the selector</th></tr><tr><td>1</td><td>97</td></tr><tr><td>2</td><td>91</td></tr><tr><td>3</td><td>74</td></tr><t…

[10] Respiratory Protection in the Workplace - A Guide for Employers

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# Respiratory Protection in the Workplace A Guide for Employers Respirators are protective devices-used as a last resort-to reduce workers' harmful exposures to airborne hazards, including oxygen-deficient atmospheres. ## What is a Harmful Exposure? Airborne harmful exposures to your employees can be in the form of: • Dusts, fumes, mists, smoke, vapors or gases that are: ○ In excess of any permissible limit prescribed by T8CCR, section 5155. ○ Of such a nature by inhalation as to result in, or have a probability to result in, injury, illness, disease, impairment or loss of function. . Oxygen-deficient atmospheres, which occur when there is less than 19.5% oxygen present. ## How to Identify Harmful Exposures There can be a number of things to consider when trying to accurately determine what your employees' airborne hazardous contaminant exposures are. The following is a brief overview. ## Factors in Assessing Respiratory Hazards • Identify the respiratory hazards your employees are exposed to and determine what the corresponding Cal/OSHA allowable exposure levels are. A good place to start is the SDS for each of the materials your employees work with. - There may be instances where there are no assigned Cal/OSHA exposure limits, in which case there may be other occupational exposure limits, such as NIOSH RELS ## Some important points to take from section 5155, Airborne Contaminants - These are assigned concentration limits to airborne contaminants that nearly all workers may be exposed to daily during a 40-hour workweek for a working lifetime without adverse effect. Also, because of variation in individual susceptibility, an occasional worker may suffer discomfort or aggravation of a preexisting condition or occupational disease upon exposure to concentrations even below the assigned exposure limits. • Harmful exposure to any substance not listed must be controlled in accordance with T8CCR, section 5141, which may include use of respiratory protec…

[11] MNOSHA Permissible Exposure Limits

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# SUBPART Z -- TOXIC AND HAZARDOUS SUBSTANCES 1910.1000-AIR CONTAMINANTS (cont.) Substituting this information in the formula, we have: (2 x 150+2 x 75 +4 x 50) ÷ 8 = 81.25 ppm Since 81.25 ppm is less than 100 ppm, the 8-hour time weighted average limit, the exposure is acceptable. (2) (i) in case of a mixture of air contaminants an employer shall compute the equivalent exposure as follows: E = (C₁ + L₁) + (C₁₂ ÷ L₂) + . . . (C ÷ L - Where: - E is the equivalent exposure for the mixture. C is the concentration of a particular contaminant. L is the exposure limit for that substance specified in Subpart Z of 29 CFR part 1910. The value of E shall not exceed unity (1). m (ii) To illustrate the formula prescribed in paragraph (d)(2)(i) of this section, consider the following exposures: <table><tr><th>Substance</th><th>Actual concentration of 8 hour exposure (ppm)</th><th>8 hr. TWA PEL (ppm)</th></tr><tr><td></td><td>500</td><td>1000</td></tr><tr><td>BCD</td><td>45</td><td>200</td></tr><tr><td></td><td>40</td><td>200</td></tr><tr><td colspan="3">Substituting in the formula, we have: m = 500 ÷ 1000 + 45 ÷ 200 + 40 ÷ 200 E = 0.500+ 0.225 +0.200 E = 0.925</td></tr></table> - Since Em is less than unity (1), the exposure combination is within acceptable limits. (e) To achieve compliance with paragraphs (a) through (d) of this section, administrative or engineering controls must first be determined and implemented whenever feasible. When such controls are not feasible to achieve full compliance, protective equipment or any other protective measures shall be used to keep the exposure of employees to air contaminants within the limits prescribed in this section. Any equipment and/or technical measures used for this purpose must be approved for each particular use by a competent industrial hygienist or other technically qualified person. Whenever respirators are used, their use shall comply with § 1910.134. (f) Effective dates. The effective date for the permiss…

[12] HOMAX TEX»PRO™ Interior Wall & Ceiling Heavy Texture

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# Section 6. Accidental release measures (cont.) ## Precautions for safe handling (cont.) Product code 00444470 Date of issue 4 May 2025 Version 6 Product name TP40 HOMAX TEXPRO HEAVY TEXTURE ORANGE PEEL # Section 7. Handling and storage Conditions for safe storage, : Do not store below the following temperature: 5°C (41°F). Store in accordance with including any local regulations. Store in original container protected from direct sunlight in a dry, cool incompatibilities and well-ventilated area, away from incompatible materials (see Section 10) and food and drink. Store locked up. Keep container tightly closed and sealed until ready for use. Containers that have been opened must be carefully resealed and kept upright to prevent leakage. Do not store in unlabeled containers. Use appropriate containment to avoid environmental contamination. ## Section 8. Exposure controls/personal protection ## Control parameters Occupational exposure limits <table><tr><th>Ingredient name</th><th>Exposure limits</th></tr><tr><td>Limestone Talc not containing asbestiform fibres crystalline silica, respirable powder (&lt;10 microns)</td><td>OSHA PEL (United States, 5/2018) TWA 8 hours: 15 mg/m3. Form: Total dust. TWA 8 hours: 5 mg/m3. Form: Respirable fraction. ACGIH TLV (United States, 1/2024) TWA 8 hours: 2 mg/m3. Form: Respirable fraction. OSHA PEL Z3 (United States) TWA: 2 mg/m3. ACGIH TLV (United States, 1/2024) [Silica, crystalline] TWA 8 hours: 0.025 mg/m³. Form: Respirable fraction. OSHA PEL Z3 (United States, 6/2016) TWA 8 hours: 250 / (%SiO2+5) mppcf. Form: Respirable. TWA 8 hours: 10 / (%SiO2+2) mg/m3. Form: Respirable.</td></tr></table> <table><tr><th colspan="4">Key to abbreviations</th></tr><tr><td>A</td><td>= Acceptable Maximum Peak</td><td>S</td><td>= Potential skin absorption</td></tr><tr><td>ACGIH</td><td>= American Conference of Governmental Industrial Hygienists.</td><td>SR</td><td>= Respiratory sensitization</td></tr><tr><td>C</td><td>= Ceiling Limit…

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