Safety Standards for Agriculture


Respiratory Hazards
Chapter 296-307 WAC, Part Y-6

WAC 296-307-624

Scope

This part applies only if your employees:

  • Are exposed to a respiratory hazard

    OR

  • Could be exposed to one of the specific hazards listed below.

This part applies to any workplace with potential or actual employee exposure to respiratory hazards. It requires you to protect employees from respiratory hazards by applying this protection strategy:

  • Evaluate employee exposures to determine if controls are needed
  • Use feasible controls. For example, enclose or confine the operation, use ventilation systems, or substitute with less toxic material
  • Use respirators if controls are not feasible or if they cannot completely remove the hazard.

Definition:

Exposed or exposure:

The contact an employee has with a toxic substance, harmful physical agent or oxygen deficient condition, whether or not protection is provided by respirators or other personal protective equipment (PPE). Exposure can occur through various routes of entry, such as inhalation, ingestion, skin contact, or skin absorption.

Note:

  • Examples of substances that may be respiratory hazards when airborne include:
    • - Chemicals listed in Table 3
    • - Any substance
      • Listed in the latest edition of the NIOSH Registry of Toxic Effects of Chemical Substances
      • For which positive evidence of an acute or chronic health hazard exists through tests conducted by, or known to, the employer
      • That may pose a hazard to human health as stated on a material safety data sheet kept by, or known to, the employer

      - Atmospheres considered oxygen deficient

    • - Biological agents such as harmful bacteria, viruses or fungi
      • Examples include airborne TB aerosols and anthrax
  • - Pesticides with a label requirement for respirator use
  • - Chemicals used as crowd control agents such as pepper spray
  • - Chemicals present at clandestine drug labs.
  • These substances can be airborne as dusts, fibers, fogs, fumes, mists, gases, smoke, sprays, vapors, or aerosols.

Reference:

  • Substances in Table 3 that are marked with an X in the "skin" column may require personal protective equipment (PPE). See WAC 296-307-100, Personal protective equipment, for additional information and requirements.
  • If any of the following hazards are present in your workplace, you will need both this part and any of the following specific rules that apply:

Hazard

Acrylonitrile

Arsenic (inorganic)

Asbestos

Benzene

Butadiene

Cadmium

Carcinogens

Coke ovens

Cotton dust

1,2-Dibromo-3-chloropropane

Ethylene oxide

Formaldehyde

Lead

Methylene chloride

Methylenedianiline

Thiram

Vinyl chloride

Statutory Authority: RCW 49.17.010, .040, .050, and .060. 06-08-087(Order 05-12), § 296-307-624, filed 04/04/06, effective 09/01/06. Statutory Authority: RCW 49.19.010, .040, .050, and .060. 05-01-066 (Order 04-19), § 296-307-624, filed 12/21/04, effective 04/02/05.]

WAC 296-307-626

SUMMARY

Evaluate and control employee exposures

Your responsibility:

To protect your employees from exposure to respiratory hazards in the workplace by identifying and controlling the hazards.

You must

WAC 296-307-62615 Use respirators

[Statutory Authority: RCW 49.19.010, .040, .050, and .060. 05-01-066 (Order 04-19), § 296-307-626, filed 12/21/04, effective 04/02/05.]

WAC 296-307-62605

Identify and evaluate respiratory hazards

You must

  • Make sure employees are protected from potentially hazardous exposure while you perform your evaluation
  • Perform your evaluation without considering the protection provided to employees by a respirator
  • Determine the form of the hazard, such as dust, mist, gas, oxygen deficiency, or biological agent
  • Make sure you consider:
    • - Potential emergency and rescue situations that may occur, such as equipment or power failures, uncontrolled chemical reactions, fire, explosion, or human error
    • - Workplace conditions such as work processes, types of material, control methods, work practices and environmental conditions.
  • Determine or reasonably estimate whether any employee is or could be exposed to any of the following:
    • - Any airborne substance above a permissible exposure limit (PEL) listed in Table 3
    • - A substance at or above the action level (AL) specified in the rule for that substance
    • - Any other respiratory hazard.
  • Use any of the following to determine employee exposure:
    • - Information that would allow an estimate of the level of employee exposure, such as MSDSs or pesticide labels, observations, measurements or calculations
    • - Data demonstrating that a particular product, material or activity cannot result in employee exposure at or above the AL or PEL
    • - Personal air samples that represent an employee's usual or worst case exposure for the entire shift.

Note:

  • Rules for specific substances may contain additional requirements for determining employee exposure.
  • Use methods of sampling and analysis that have been validated by the laboratory performing the analysis.
  • Samples from a representative group of employees may be used for other employees performing the same work activities when the duration and level of exposure are similar.

You must

  • Consider the atmosphere to be immediately dangerous to life or health (IDLH) when you cannot determine or reasonably estimate employee exposure
  • Make sure employee exposure, to 2 or more substances with additive health effects, is evaluated using this formula:

E m

=

C 1

L 1

+

C 2

L 2

+

. . .

+

C n

L n

The symbol

Is the . . .

E

Equivalent exposure for the mixture. When the value of E is greater than 1, a respiratory hazard is present.

C

Concentration of a particular substance.

L

TWA, STEL, or ceiling for that substance from Table 3.

[Statutory Authority: RCW 49.19.010, .040, .050, and .060. 05-01-066 (Order 04-19), § 296-307-62605, filed 12/21/04, effective 04/02/05.]

WAC 296-307-62610

Control employee exposures

You must

  • Use feasible controls to protect employees from exposure to respiratory hazards by:
    • - Reducing employee exposure to a level that removes the respiratory hazard, such as to a level below the permissible exposure limit (PEL) in Table 3;
      OR
    • - Reducing the exposure to the lowest achievable level, when the respiratory hazard cannot be removed.

  Note:

  • The following table gives you examples of control methods.

Table 1

Examples of Possible Controls

Control:

For example:

Using a different chemical (substitution)

  • Choose a chemical with a lower evaporation rate or vapor pressure.
  • Choose a chemical without hazardous ingredients.

Changing a process to lessen emissions

  • Use hand rolling or paint dipping instead of paint spraying.
  • Bolt items instead of welding them.

Separating employees from emissions areas and sources

  • Use control rooms.
  • Build an enclosure around process machinery or other emissions sources.
  • Automate a process.

Removing emissions at or near the source (local exhaust ventilation)

  • Install exhaust hoods or slots to capture emissions.
  • Use an exhausted enclosure (like a blasting cabinet or laboratory hood).

Diluting and removing emissions in the work area (general exhaust ventilation)

  • Allow natural air movement to create an adequate airflow through an area.
  • Use mechanical fans

Modify work practices

  • Change the position of the worker relative to the work so fumes, vapors, or smoke do not go into their face.

Rotate employees

  • - Some specific rules prohibit the use of this control method
  • Move employees to another job that is without exposure, on a schedule to keep their total exposure below the permissible exposure limit.

[Statutory Authority: RCW 49.19.010, .040, .050, and .060. 05-01-066 (Order 04-19), § 296-307-62610, filed 12/21/04, effective 04/02/05.]

WAC 296-307-62615

Use respirators

You must

  • Require employees to use respiratory protection when respiratory hazards have not been removed using feasible controls. For example, use respirators at any of the following times:
    • - While controls are being evaluated or put in place
    • - When the respiratory hazard is not completely removed
    • - When controls are not feasible.

Reference:

See WAC 296-307-594, Respirators, for respirator program requirements.

[Statutory Authority: RCW 49.19.010, .040, .050, and .060. 05-01-066 (Order 04-19), § 296-307-62615, filed 12/21/04, effective 04/02/05.]

WAC 296-307-62620

Notify employees

You must

  • Notify employees who are or may be exposed to respiratory hazards, as specified in Table 2.

Note:

  • The notification may be provided either individually, to a group, or by posting of results in an appropriate location that's accessible to affected employees.

Table 2

Notification Requirements

Notify employees of:

As follows:

Any exposure result above a permissible exposure limit (PEL)

Within 5 business days, after the employee's exposure result is known to the employer

The corrective action being taken to reduce employee exposure to or below the PEL

Within 15 business days, after the employee's exposure result is known to the employer

and

 

The schedule for completion of the corrective action and any reasons why exposures cannot be lowered to below the PEL

 

An exposure to these substances:

In writing, as specified in the rule specific to the substance

  • Acrylonitrile

 

  • Arsenic (inorganic)

 

  • Asbestos

 

  • Benzene

 

  • Butadiene

 

  • Cadmium

 

  • Coke oven emissions

 

  • Cotton dust

 

  • 1,2-Dibromo-3-chloropropane

 

  • Ethylene oxide

 

  • Formaldehyde

 

  • Lead

 

  • Methylene chloride

 

  • Methylenedianiline

 

  • Vinyl chloride

 

[Statutory Authority: RCW 49.19.010, .040, .050, and .060. 05-01-066 (Order 04-19), § 296-307-62620, filed 12/21/04, effective 04/02/05.]

WAC 296-307-62625

Permissible exposure limits of air contaminants

Important:

The following information applies to Table 3, Permissible Exposure Limits for Air Contaminants.

  • Exposure needs to be determined from personal air samples taken in the breathing zone or from monitoring representative of the employee's breathing zone.
  • Ppm refers to parts of vapor or gas per million parts of air by volume, at 25 degrees C and 760 mm Hg pressure.
  • Mg/m3 refers to milligrams of substance per cubic meter of air.
  • For a metal that is measured as the metal itself, only the CAS number for the metal is given. The CAS numbers for individual compounds of the metal are not provided. For more information about CAS registry numbers see the website: http://www.cas.org.
  • Time weighted averages (TWA8) represent the maximum allowed average exposure for any 8-hour time period. For work periods longer than 8 hours the TWA8 needs to be determined using the 8 continuous hours with the highest average concentration.
  • Short-term exposure limits (STEL) represent maximum allowed average exposure for any fifteen-minute period, unless another time period is noted in Table 3.
  • The ceiling represents the maximum allowed exposure for the shortest time period that can feasibly be measured.
  • An "X" in the "skin" column indicates the substance can be absorbed through the skin, either by airborne or direct contact.
  • Requirements for the use of gloves, coveralls, goggles, and other personal protective equipment can be found in WAC 296-307-100.
  • The respirable fraction of particulate is measured by sampling with a size-selector having the following characteristics:

Mean aerodynamic diameter in micrometers

Percent passing the selector

1

97

2

91

3

74

4

50

5

30

6

17

7

9

8

5

10

1

 

Table 3 "Permissible Exposure Limits for Air Contaminants"

 

WAC 296-307-628

Definitions.

Ceiling

An exposure limit, measured over the shortest time period feasible, that must not be exceeded during any part of the employee's workday.

Dust

Solid particles suspended in air. Dusts are generated by handling, drilling, crushing, grinding, rapid impact, detonation, or decrepitation of organic or inorganic materials such as rock, ore, metal, coal, wood, grain, etc.

Exposed or exposure

The contact an employee has with a toxic substance, harmful physical agent or oxygen deficient condition. Exposure can occur through various routes of entry, such as inhalation, ingestion, skin contact, or skin absorption.

Fume

Solid particles suspended in air, generated by condensation from the gaseous state, generally after volatilization from molten metals, etc.

Gas

A normally formless fluid which can be changed to the liquid or solid state by the effect of increased pressure or decreased temperature or both.

Mist

Liquid droplets suspended in air, generated by condensation from the gaseous to the liquid state or by breaking up a liquid into a dispersed state, such as by splashing, foaming, spraying or atomizing.

Oxygen deficient

An atmosphere with an oxygen content below 19.5% by volume.

Permissible exposure limits (PEL)

Permissible exposure limits (PELs) are employee exposures to toxic substances or harmful agents that must not be exceeded. PELs are specified in applicable WISHA rules.

Short-term exposure limit (STEL)

An exposure limit averaged over a short time period (usually measured for 15 minutes) that must not be exceeded during any part of an employee's workday.

Time weighted average (TWA8)

An exposure limit averaged over 8 hours that must not be exceeded during an employee's workday.

Toxic substance

Any chemical substance or biological agent, such as bacteria, virus, and fungus, which is any of the following:

  • Listed in the latest edition of the National Institute for Occupational Safety and Health (NIOSH) Registry of Toxic Effects of Chemical Substances (RTECS)
  • Shows positive evidence of an acute or chronic health hazard in testing conducted by, or known to, the employer.

The subject of a material safety data sheet kept by or known to the employer showing the material may pose a hazard to human health.

Vapor

The gaseous form of a substance that is normally in the solid or liquid state.

[Statutory Authority: RCW 49.19.010, .040, .050, and .060. 05-01-066 (Order 04-19), § 296-307-628, filed 12/21/04, effective 04/02/05.]

 

 

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