(a) This section, in its entirety, applies to the control of
employee exposure to cotton dust in all workplaces where employees
engage in yarn manufacturing, engage in slashing and weaving
operations, or work in waste houses for textile operations.
(b) This section does not apply to the handling or processing
of woven or knitted materials; to maritime operations covered
by chapters 296-56
and 296-304
WAC; to harvesting or ginning of cotton; or to the construction
industry.
(c) Only subsection (8) Medical surveillance, subsection (11)
(b) Medical surveillance, subsection (11)(c) Availability, subsection
(11)(d) Transfer of records, and Appendices B, C, and D of this
section apply in all work places where employees exposed to
cotton dust engage in cottonseed processing or waste processing
operations.
(d) This section applies to yarn manufacturing and slashing
and weaving operations exclusively using washed cotton (as defined
by subsection (14) of this section) only to the extent specified
by subsection (14) of this section.
(e) This section, in its entirety, applies to the control of
all employees exposure to the cotton dust generated in the preparation
of washed cotton from opening until the cotton is thoroughly
wetted.
(f) This section does not apply to knitting, classing or warehousing
operations except that employers with these operations, if requested
by WISHA, shall grant WISHA access to their employees and workplaces
for exposure monitoring and medical examinations for purposes
of a health study to be performed by WISHA on a sampling basis.
(2) Definitions applicable to this section:
(a) “Blow down” - the cleaning of equipment
and surfaces with compressed air.
(b) “Blow off” - the use of compressed air
for cleaning of short duration and usually for a specific machine
or any portion of a machine.
(c) “Cotton dust” - dust present in the
air during the handling or processing of cotton, which may contain
a mixture of many substances including ground-up plant matter,
fiber, bacteria, fungi, soil, pesticides, noncotton plant matter
and other contaminants which may have accumulated with the cotton
during the growing, harvesting and subsequent processing or
storage periods. Any dust present during the handling and processing
of cotton through the weaving or knitting of fabrics, and dust
present in other operations or manufacturing processes using
raw or waste cotton fibers or cotton fiber byproducts from textile
mills are considered cotton dust within this definition. Lubricating
oil mist associated with weaving operations is not considered
cotton dust.
(d) “Director” - the director of labor and
industries or his authorized representative.
(e) “Equivalent instrument” - a cotton dust
sampling device that meets the vertical elutriator equivalency
requirements as described in subsection (4)(a)(iii) of this
section.
(f) “Lint-free respirable cotton dust” -
particles of cotton dust of approximately 15 microns or less
aerodynamic equivalent diameter.
(g) “Vertical elutriator cotton dust sampler”
or “vertical elutriator” - a dust sampler
which has a particle size cut-off at approximately 15 microns
aerodynamic equivalent diameter when operating at the flow rate
of 7.4 ±0.2 liters per minute.
(h) “Waste processing” - waste recycling
(sorting, blending, cleaning and willowing) and garnetting.
(i) “Yarn manufacturing” - all textile mill
operations from opening to, but not including, slashing and
weaving.
(3) Permissible exposure limits and action levels.
(a) Permissible exposure limits (PEL).
(i) The employer shall assure that no employee who is exposed
to cotton dust in yarn manufacturing and cotton washing operations
is exposed to airborne concentrations of lint-free respirable
cotton dust greater than 200 mg/m3 mean concentration, averaged
over an eight-hour period, as measured by a vertical elutriator
or an equivalent instrument.
(ii) The employer shall assure than no employee who is exposed
to cotton dust in textile mill waste house operations or is
exposed in yarn manufacturing to dust from “lower grade
washed cotton” as defined in subsection (14)(e) of this
section is exposed to airborne concentrations of lint-free
respirable cotton dust greater than 500 mg/m3 mean concentration,
averaged over an eight-hour period, as measured by a vertical
elutriator or an equivalent instrument.
(iii) The employer shall assure that no employee who is exposed
to cotton dust in the textile processes known as slashing
and weaving is exposed to airborne concentrations of lint-free
respirable cotton dust greater than 750 m/m3 mean concentration,
averaged over an eight-hour period, as measured by a vertical
elutriator or an equivalent instrument.
(b) Action levels.
(i) The action level for yarn manufacturing and cotton washing
operations is an airborne concentration of lint-free respirable
cotton dust of 100 m/m3 mean concentration, averaged over
an eight-hour period, as measured by a vertical elutriator
or an equivalent instrument.
(ii) The action level for waste houses for textile operations
is an airborne concentration of lint-free respirable cotton
dust of 250 mg/m3 mean concentration, averaged over an eight-hour
period, as measured by a vertical elutriator or an equivalent
instrument.
(iii) The action level for the textile processes known as
slashing and weaving is an airborne concentration of lint-free
respirable cotton dust of 375 mg/m3 mean concentration, averaged
over an eight-hour period, as measured by a vertical elutriator
or an equivalent instrument.
(4) Exposure monitoring and measurement.
(a) General.
(i) For the purposes of this section, employee exposure is
that exposure which would occur if the employee were not using
a respirator.
(ii) The sampling device to be used shall be either the vertical
elutriator cotton dust sampler or an equivalent instrument.
(iii) If an alternative to the vertical elutriator cotton
dust sampler is used, the employer shall establish equivalency
by demonstrating that the alternative sampling devices:
(A) It collects respirable particulates in the same range
as the vertical elutriator (approximately 15 microns);
(B) Replicate exposure data used to establish equivalency
are collected in side-by-side field and laboratory comparisons;
and
(C) A minimum of 100 samples over the range of 0.5 to 2
times the permissible exposure limit are collected, and
ninety percent of these samples have an accuracy range of
plus or minus twenty-five percent of the vertical elutriator
reading with a ninety-five percent confidence level as demonstrated
by a statistically valid protocol. (An acceptable protocol
for demonstrating equivalency is described in Appendix E
of this section.)
(iv) WISHA will issue a written opinion stating that an instrument
is equivalent to a vertical elutriator cotton dust sampler
if:
(A) A manufacturer or employer requests an opinion in writing
and supplies the following information:
(I) Sufficient test data to demonstrate that the instrument
meets the requirements specified in this paragraph and
the protocol specified in Appendix E of this section;
(II) Any other relevant information about the instrument
and its testing requested by WISHA; and
(III) A certification by the manufacturer or employer
that the information supplied is accurate, and
(B) If WISHA finds, based on information submitted about
the instrument, that the instrument meets the requirements
for equivalency specified by this subsection.
(b) Initial monitoring. Each employer who has a place of
employment within the scope of subsections (1)(a), (d) or
(e) of this section shall conduct monitoring by obtaining
measurements which are representative of the exposure of all
employees to airborne concentrations of lint-free respirable
cotton dust over an eight-hour period. The sampling program
shall include at least one determination during each shift
for each work area.
(c) Periodic monitoring.
(i) If the initial monitoring required by (4)(b) of this
section or any subsequent monitoring reveals employee exposure
to be at or below the permissible exposure limit, the employer
shall repeat the monitoring for those employees at least annually.
(ii) If the initial monitoring required by (4)(b) of this
section or any subsequent monitoring reveals employee exposure
to be above the PEL, the employer shall repeat the monitoring
for those employees at least every six months.
(iii) Whenever there has been a production, process, or control
change which may result in new or additional exposure to cotton
dust, or whenever the employer has any other reason to suspect
an increase in employee exposure, the employer shall repeat
the monitoring and measurements for those employees affected
by the change or increase.
(d) Employee notification.
(i) Within 15 working days after the receipt of monitoring
results, the employer shall notify each employee in writing
of the exposure measurements which represent that employee's
exposure.
(ii) Whenever the results indicate that the employee's exposure
exceeds the applicable permissible exposure limit specified
in subsection (3) of this section, the employer shall include
in the written notice a statement that the permissible exposure
limit was exceeded and a description of the corrective action
taken to reduce exposure below the permissible exposure limit.
(5) Methods of compliance.
(a) Engineering and work practice controls. The employer shall
institute engineering and work practice controls to reduce and
maintain employee exposure to cotton dust at or below the permissible
exposure limit specified in subsection (3) of this section,
except to the extent that the employer can establish that such
controls are not feasible.
(b) Whenever feasible engineering and work practice controls
are not sufficient to reduce employee exposure to or below the
permissible exposure limit, the employer shall nonetheless institute
these controls to immediately reduce exposure to the lowest
feasible level, and shall supplement these controls with the
use of respirators which shall comply with the provisions of
subsection (6) of this section.
(c) Compliance program.
(i) Where the most recent exposure monitoring data indicates
that any employee is exposed to cotton dust levels greater
than the permissible exposure limit, the employer shall establish
and implement a written program sufficient to reduce exposures
to or below the permissible exposure limit solely by means
of engineering controls and work practices as required by
(a) of this subsection.
(ii) The written program shall include at least the following:
(A) A description of each operation or process resulting
in employee exposure to cotton dust;
(B) Engineering plans and other studies used to determine
the controls for each process;
(C) A report of the technology considered in meeting the
permissible exposure limit;
(D) Monitoring data obtained in accordance with subsection
(4) of this section;
(E) A detailed schedule for development and implementation
of engineering and work practice controls, including exposure
levels projected to be achieved by such controls;
(F) Work practice program; and
(G) Other relevant information.
(iii) The employer's schedule as set forth in the compliance
program, shall project completion of the implementation of
the compliance program no later than March 27, 1984 or as
soon as possible if monitoring after March 27, 1984 reveals
exposures over the PEL, except as provided in (13)(b)(ii)(B)
of this section.
(iv) The employer shall complete the steps set forth in his
program by the dates in the schedule.
(v) Written programs shall be submitted, upon request, to
the director, and shall be available at the worksite for examination
and copying by the director, and any affected employee or
their designated representatives.
(vi) The written programs required under subsection (5)(c)
of this section shall be revised and updated at least every
six months to reflect the current status of the program and
current exposure levels.
(d) Mechanical ventilation. When mechanical ventilation is
used to control exposure, measurements which demonstrate the
effectiveness of the system to control exposure, such as capture
velocity, duct velocity, or static pressure shall be made at
reasonable intervals.
(6) Use of respirators.
(a) General. For employees who use respirators required by
this section, the employer must provide respirators that comply
with the requirements of this section. Respirators must be used
during:
(i) Periods necessary to install or implement feasible engineering
controls and work-practice controls;
(ii) Maintenance and repair activities for which engineering
and work-practice controls are not feasible;
(iii) Work operations for which feasible engineering and
work-practice controls are not yet sufficient to reduce employee
exposure to or below the permissible exposure limits;
(iv) Work operations specified under subsection (7)(a) of
this section;
(v) Periods for which an employee requests a respirator.
(b) Respirator program.
(i) The employer must develop, implement and maintain a respiratory
protection program as required by chapter
296-842 WAC,
(ii) Whenever a physician determines that an employee who
works in an area in which the cotton-dust concentration exceeds
the PEL is unable to use a respirator, including a powered
air-purifying respirator, the employee must be given the opportunity
to transfer to an available position, or to a position that
becomes available later, that has a cotton-dust concentration
at or below the PEL. The employer must ensure that such employees
retain their current wage rate or other benefits as a result
of the transfer.
(c) Respirator selection. The employer must:
(i) Select and provide to employees the appropriate respirators
by following requirements in this section and WAC 296-842-13005,
found in the respirator rule.
(ii) Provide employees with a powered air-purifying respirator
(PAPR) when the employee chooses to use a PAPR instead of
a negative-pressure air-purifying respirator, and the PAPR
will provide adequate protection.
(iii) Limit the use of filtering facepiece respirators for
protection against cotton dust to concentrations less than
or equal to 5 times (5x) the PEL.
(iv) Provide high-efficiency particulate air (HEPA) filters
or N-, R-, or P-100 series filters for powered air-purifying
respirators (PAPRs) and negative-pressure air-purifying respirators
when used in cotton dust concentrations greater than 10 times
(10x) the PEL.
(7) Work practices. Each employer shall, regardless of the level
of employee exposure, immediately establish and implement a written
program of work practices which shall minimize cotton dust exposure.
The following shall be included where applicable:
(a) Compressed air “blow down” cleaning shall be
prohibited, where alternative means are feasible. Where compressed
air is used for cleaning, the employees performing the “blow
down” or “blow off” shall wear suitable respirators.
Employees whose presence is not required to perform “blow
down” or “blow off” shall be required to leave
the area affected by the “blow down” or “blow
off” during this cleaning operation.
(b) Cleaning of clothing or floors with compressed air shall
be prohibited.
(c) Floor sweeping shall be performed with a vacuum or with
methods designed to minimize dispersal of dust.
(d) In areas where employees are exposed to concentrations
of cotton dust greater than the permissible exposure limit,
cotton and cotton waste shall be stacked, sorted, baled, dumped,
removed or otherwise handled by mechanical means, except where
the employer can show that it is infeasible to do so. Where
infeasible, the method used for handling cotton and cotton waste
shall be the method which reduces exposure to the lowest level
feasible.
(8) Medical surveillance.
(a) General.
(i) Each employer covered by the standard shall institute
a program of medical surveillance for all employees exposed
to cotton dust.
(ii) The employer shall assure that all medical examinations
and procedures are performed by or under the supervision of
a licensed physician and are provided without cost to the
employee.
(iii) Persons other than licensed physicians, who administer
the pulmonary function testing required by this section shall
have completed a NIOSH approved training course in spirometry.
(b) Initial examinations. The employer shall provide medical
surveillance to each employee who is or may be exposed to cotton
dust. For new employees' this examination shall be provided
prior to initial assignment. The medical surveillance shall
include at least the following:
(i) A medical history;
(ii) The standardized questionnaire contained in WAC
296-62-14537; and
(iii) A pulmonary function measurement, including a determination
of forced vital capacity (FVC) and forced expiratory volume
in one second (FEV1), the FEV1/FVC ratio,
and the percentage that the measured values of FEV1
and FVC differ from the predicted values, using the standard
tables in WAC
296-62-14539. These determinations shall be made for each
employee before the employee enters the workplace on the first
day of the work week, preceded by at least thirty-five hours
of no exposure to cotton dust. The tests shall be repeated
during the shift, no less than four hours and no more than
ten hours after the beginning of the work shift; and, in any
event, no more than one hour after cessation of exposure.
Such exposure shall be typical of the employee's usual workplace
exposure. The predicted FEV1 and FVC for blacks
shall be multiplied by 0.85 to adjust for ethnic differences.
(iv) Based upon the questionnaire results, each employee
shall be graded according to Schilling's byssinosis classification
system.
(c) Periodic examinations.
(i) The employer shall provide at least annual medical surveillance
for all employees exposed to cotton dust above the action
level in yarn manufacturing, slashing and weaving, cotton
washing and waste house operations. The employer shall provide
medical surveillance at least every two years for all employees
exposed to cotton dust at or below the action level, for all
employees exposed to cotton dust from washed cotton (except
from washed cotton defined in subsection (9)(c) of this section),
and for all employees exposed to cotton dust in cottonseed
processing and waste processing operations. Periodic medical
surveillance shall include at least an update of the medical
history, standardized questionnaire (Appendix B-111), Schilling
byssinosis grade, and the pulmonary function measurements
in (b)(iii) of this subsection.
(ii) Medical surveillance as required in (c)(i) of this subsection
shall be provided every six months for all employees in the
following categories:
(A) An FEV1 of greater than eighty percent of
the predicted value, but with an FEV1 decrement
of five percent or 200 ml. on a first working day;
(B) An FEV1 of less than eighty percent of the
predicted value; or
(C) Where, in the opinion of the physician, any significant
change in questionnaire findings, pulmonary function results,
or other diagnostic tests have occurred.
(iii) An employee whose FEV1 is less than sixty
percent of the predicted value shall be referred to a physician
for a detailed pulmonary examination.
(iv) A comparison shall be made between the current examination
results and those of previous examinations and a determination
made by the physician as to whether there has been a significant
change.
(d) Information provided to the physician. The employer shall
provide the following information to the examining physician:
(i) A copy of this regulation and its appendices;
(ii) A description of the affected employee's duties as they
relate to the employee's exposure;
(iii) The employee's exposure level or anticipated exposure
level;
(iv) A description of any personal protective equipment used
or to be used; and
(v) Information from previous medical examinations of the
affected employee which is not readily available to the examining
physician.
(e) Physician's written opinion.
(i) The employer shall obtain and furnish the employee with
a copy of a written opinion from the examining physician containing
the following:
(A) The results of the medical examination and tests including
the FEV1, FVC, and FEV1/FVC ratio;
(B) The physician's opinion as to whether the employee
has any detected medical conditions which would place the
employee at increased risk of material impairment of the
employee's health from exposure to cotton dust;
(C) The physician's recommended limitations upon the employee's
exposure to cotton dust or upon the employee's use of respirators
including a determination of whether an employee can wear
a negative pressure respirator, and where the employee cannot,
a determination of the employee's ability to wear a powered
air purifying respirator; and
(D) A statement that the employee has been informed by
the physician of the results of the medical examination
and any medical conditions which require further examination
or treatment.
(ii) The written opinion obtained by the employer shall not
reveal specific findings or diagnoses unrelated to occupational
exposure.
(9) Employee education and training.
(a) Training program.
(i) The employer shall provide a training program for all
employees exposed to cotton dust and shall assure that each
employee is informed of the following:
(A) The acute and long term health hazards associated with
exposure to cotton dust;
(B) The names and descriptions of jobs and processes which
could result in exposure to cotton dust at or above the
PEL.
(C) The measures, including work practices required by
subsection (7) of this section, necessary to protect the
employee from exposures in excess of the permissible exposure
limit;
(D) The purpose, proper use, limitations, and other training
requirements for respiratory protection as required by subsection
(6) of this section and chapter 296-842
WAC (see WAC
296-842-11005, 296-842-16005
and 296-842-19005;
(E) The purpose for and a description of the medical surveillance
program required by subsection (8) of this section and other
information which will aid exposed employees in understanding
the hazards of cotton dust exposure; and
(F) The contents of this standard and its appendices.
(ii) The training program shall be provided prior to initial
assignment and shall be repeated annually for each employee
exposed to cotton dust, when job assignments or work processes
change and when employee performance indicates a need for
retraining.
(b) Access to training materials.
(i) Each employer shall post a copy of this section with
its appendices in a public location at the workplace, and
shall, upon request, make copies available to employees.
(ii) The employer shall provide all materials relating to
the employee training and information program to the director
upon request.
(10) Signs. The employer shall post the following warning sign
in each work area where the permissible exposure limit for cotton
dust is exceeded:
WARNING
COTTON DUST WORK AREA
MAY CAUSE ACUTE OR DELAYED LUNG INJURY
(BYSSINOSIS)
RESPIRATORS REQUIRED IN THIS AREA
(11) Recordkeeping.
(a) Exposure measurements.
(i) The employer shall establish and maintain an accurate
record of all measurements required by subsection (4) of this
section.
(ii) The record shall include:
(A) A log containing the items listed in WAC
296-62-14535 (4)(a), and the dates, number, duration,
and results of each of the samples taken, including a description
of the procedure used to determine representative employee
exposures;
(B) The type of protective devices worn, if any, and length
of time worn; and
(C) The names, social security number, job classifications,
and exposure levels of employees whose exposure the measurement
is intended to represent.
(iii) The employer shall maintain this record for at least
twenty years.
(b) Medical surveillance.
(i) The employer shall establish and maintain an accurate
medical record for each employee subject to medical surveillance
required by subsection (8) of this section.
(ii) The record shall include:
(A) The name and social security number and description
of the duties of the employee;
(B) A copy of the medical examination results including
the medical history, questionnaire response, results of
all tests, and the physician's recommendation;
(C) A copy of the physician's written opinion;
(D) Any employee medical complaints related to exposure
to cotton dust;
(E) A copy of this standard and its appendices, except
that the employer may keep one copy of the standard and
the appendices for all employees, provided that he references
the standard and appendices in the medical surveillance
record of each employee; and
(F) A copy of the information provided to the physician
as required by subsection (8)(d) of this section.
(iii) The employer shall maintain this record for at least
twenty years.
(c) Availability.
(i) The employer shall make all records required to be maintained
by subsection (11) of this section available to the director
for examination and copying.
(ii) Employee exposure measurement records and employee medical
records required by this subsection shall be provided upon
request to employees, designated representatives, and the
assistant director in accordance with chapter
296-802 WAC.
(d) Transfer of records.
(i) Whenever the employer ceases to do business, the successor
employer shall receive and retain all records required to
be maintained by subsection (11) of this section.
(ii) Whenever the employer ceases to do business, and there
is no successor employer to receive and retain the records
for the prescribed period, these records shall be transmitted
to the director.
(iii) At the expiration of the retention period for the records
required to be maintained by this section, the employer shall
notify the director at least three months prior to the disposal
of such records and shall transmit those records to the director
if he requests them within that period.
(iv) The employer shall also comply with any additional requirements
involving transfer of records set forth in chapter
296-802 WAC.
(12) Observation of monitoring.
(a) The employer shall provide affected employees or their
designated representatives an opportunity to observe any measuring
or monitoring of employee exposure to cotton dust conducted
pursuant to subsection (4) of this section.
(b) Whenever observation of the measuring or monitoring of
employee exposure to cotton dust requires entry into an area
where the use of personal protective equipment is required,
the employer shall provide the observer with and assure the
use of such equipment and shall require the observer to comply
with all other applicable safety and health procedures.
(c) Without interfering with the measurement, observers shall
be entitled to:
(i) An explanation of the measurement procedures;
(ii) An opportunity to observe all steps related to the measurement
of airborne concentrations of cotton dust performed at the
place of exposure; and
(iii) An opportunity to record the results obtained.
(13) Washed cotton.
(a) Exemptions. Cotton, after it has been washed by the processes
described in this section is exempt from all or parts of this
section as specified if the requirements of this section are
met.
(b) Initial requirements.
(i) In order for an employer to qualify as exempt or partially
exempt from this standard for operations using washed cotton,
the employer must demonstrate that the cotton was washed in
a facility which is open to inspection by the director and
the employer must provide sufficient accurate documentary
evidence to demonstrate that the washing methods utilized
meet the requirements of this section.
(ii) An employer who handles or processes cotton which has
been washed in a facility not under the employer's control
and claims an exemption or partial exemption under this paragraph,
must obtain from the cotton washer and make available at the
worksite, to the director, or his designated representative,
to any affected employee, or to their designated representative
the following:
(A) A certification by the washer of the cotton of the
grade of cotton, the type of washing process, and that the
batch meets the requirements of this section:
(B) Sufficient accurate documentation by the washer of
the cotton grades and washing process; and
(C) An authorization by the washer that the director may
inspect the washer's washing facilities and documentation
of the process.
(c) Medical and dyed cotton. Medical grade (USP) cotton, cotton
that has been scoured, bleached and dyed, and mercerized yarn
shall be exempt from all provisions of this standard.
(d) Higher grade washed cotton. The handling or processing
of cotton classed as “low middling light spotted or better”
(color grade 52 or better and leaf grade code 5 or better according
to the 1993 USDA classification system) shall be exempt from
all provisions of the standard except requirements of subsection
(8) of this section, medical surveillance; subsection (11)(b)
through (d) of this section, recordkeeping-medical records,
and Appendices B, C, and D of this section, if they have been
washed on one of the following systems:
(i) On a continuous batt system or a rayon rinse system including
the following conditions:
(A) With water;
(B) At a temperature of no less than 60°C;
(C) With a water-to-fiber ratio of no less than 40:1; and
(D) With the bacterial levels in the wash water controlled
to limit bacterial contamination of the cotton.
(ii) On a batch kier washing system including the following
conditions:
(A) With water;
(B) With cotton fiber mechanically opened and thoroughly
prewetted before forming the cake;
(C) For low-temperature processing, at a temperature of
no less than 60°C with a water-to-fiber ratio of no less
than 40:1; or, for high-temperature processing, at a temperature
of no less than 93°C with a water-to-fiber ratio of no less
than 15:1;
(D) With a minimum of one wash cycle followed by two rinse
cycles for each batch, using fresh water in each cycle;
and
(E) With bacterial levels in the wash water controlled
to limit bacterial contamination of the cotton.
(e) Lower grade washed cotton. The handling and processing
of cotton of grades lower than “low middling light spotted,”
that has been washed as specified in (d) of this subsection
and has also been bleached, shall be exempt from all provisions
of the standard except the requirements of subsection (3)(a)
Permissible exposure limits, subsection (4) Exposure monitoring
and measurement, subsection (8) Medical surveillance, subsection
(11) Recordkeeping, and Appendices B, C and D of this section.
(f) Mixed grades of washed cotton. If more than one grade of
washed cotton is being handled or processed together, the requirements
of the grade with the most stringent exposure limit, medical
and monitoring requirements shall be followed.
(14) Appendices.
(a) Appendix B (B-I, B-II and B-III), WAC
296-62-14537, Appendix C, WAC
296-62-14539 and Appendix D, WAC
296-62-14541 are incorporated as part of this chapter and
the contents of these appendices are mandatory.
(b) Appendix A of this chapter, WAC
296-62-14535 contains information which is not intended
to create any additional obligations not otherwise imposed or
to detract from any existing obligations.
(c) Appendix E of this chapter is a protocol which may be followed
in the validation of alternative measuring devices as equivalent
to the vertical elutriator cotton dust sampler. Other protocols
may be used if it is demonstrated that they are statistically
valid, meet the requirements in subsection (4)(a)(iii) of this
section, and are appropriate for demonstrating equivalency.
WAC
296-62-14535 Appendix A--Air sampling and analytical procedures
for determining concentrations of cotton dust.
(1) Sampling locations. The sampling procedures must be designed
so that samples of the actual dust concentrations are collected
accurately and consistently and reflect the concentrations of
dust at the place and time of sampling. Sufficient number of six-hour
area samples in each distinct work area of the plant should be
collected at locations which provide representative samples of
air to which the worker is exposed. In order to avoid filter overloading,
sampling time may be shortened when sampling in dusty areas. Samples
in each work area should be gathered simultaneously or sequentially
during a normal operating period. The daily time-weighted average
(TWA) exposure of each worker can then be determined by using
the following formula:
Summation of hours spent in each location
and the dust concentration in that location.
Total hours exposed
A time-weighted average concentration should be computed for
each worker and properly logged and maintained on file for review.
(2) Sampling equipment.
(a) Sampler. The instrument selected for monitoring is the
Lumsden-Lynch vertical elutriator. It should operate at a flow
rate of 7.4 ±0.2 liters/minute. The samplers should be cleaned
prior to sampling. The pumps should be monitored during sampling.
(b) Filter holder. A three-piece cassette constructed of polystyrene
designed to hold a 37-mm diameter filter should be used. Care
must be exercised to insure that an adequate seal exists between
elements of the cassette.
(c) Filters and support pads. The membrane filters used should
be polyvinyl chloride with a 5-um pore size and 37-mm diameter.
A support pad, commonly called a backup pad, should be used
under the filter membrane in the field monitor cassette.
(d) Balance. A balance sensitive to 10 micrograms should be
used.
(3) Instrument calibration procedure. Samplers shall be calibrated
when first received from the factory, after repair, and after
receiving any abuse. The samplers should be calibrated in the
laboratory both before they are used in the field and after they
have been used to collect a large number of field samples. The
primary standard, such as a spirometer or other standard calibrating
instruments such as a wet test meter or a large bubble meter or
dry gas meter, should be used. Instructions for calibration with
the wet test meter follow. If another calibration device is selected,
equivalent procedures should be used:
(a) Level wet test meter. Check the water level which should
just touch the calibration point at the left side of the meter.
If water level is low, add water 1-2° F. warmer than room temperature
of till point. Run the meter for thirty minutes before calibration;
(b) Place the polyvinyl chloride membrane filter in the filter
cassette;
(c) Assemble the calibration sampling train;
(d) Connect the wet test meter to the train.
The pointer on the meter should run clockwise and a pressure
drop of not more than 1.0 inch of water indicated. If the pressure
drop is greater than 1.0, disconnect and check the system;
(e) Operate the system for ten minutes before starting the
calibration;
(f) Check the vacuum gauge on the pump to insure that the pressure
drop across the orifice exceeds seventeen inches of mercury;
(g) Record the following on calibration data sheets:
(i) Wet test meter reading, start and finish;
(ii) Elapsed time, start and finish (at least two minutes);
(iii) Pressure drop at manometer;
(iv) Air temperature;
(v) Barometric pressure; and
(vi) Limiting orifice number.
(h) Calculate the flow rate and compare against the flow of
7.4 ±0.2 liters/minute. If flow is between these limits, perform
calibration again, average results, and record orifice number
and flow rate. If flow is not within these limits, discard or
modify orifice and repeat procedure;
(i) Record the name of the person performing the calibration,
the date, serial number of the wet test meter, and the number
of the critical orifices being calibrated.
(4) Sampling procedure.
(a) Sampling data sheets should include a log of:
(i) The date of the sample collection;
(ii) The time of sampling;
(iii) The location of the sampler;
(iv) The sampler serial number;
(v) The cassette number;
(vi) The time of starting and stopping the sampling and the
duration of sampling;
(vii) The weight of the filter before and after sampling;
(viii) The weight of dust collected (corrected for controls);
(ix) The dust concentration measured;
(x) Other pertinent information; and
(xi) Name of person taking sample.
(b) Assembly of filter cassette should be as follows:
(i) Loosely assemble three-piece cassette;
(ii) Number cassette;
(iii) Place absorbent pad in cassette;
(iv) Weigh filter to an accuracy of 10 mg;
(v) Place filter in cassette;
(vi) Record weight of filter in log, using cassette number
for identification;
(vii) Fully assemble cassette, using pressure to force parts
tightly together;
(viii) Install plugs top and bottom;
(ix) Put shrink band on cassette, covering joint between
center and bottom parts of cassette; and
(x) Set cassette aside until shrink band dries thoroughly.
(c) Sampling collection should be performed as follows:
(i) Clean lint out of the motor and elutriator;
(ii) Install vertical elutriator in sampling locations specified
above with inlet 4-1/2 to 5-1/2 feet from floor (breathing
zone height);
(iii) Remove top section of cassette;
(iv) Install cassette in ferrule of elutriator;
(v) Tape cassette to ferrule with masking tape or similar
material for air-tight seal;
(vi) Remove bottom plug of cassette and attach hose containing
critical orifice;
(vii) Start elutriator pump and check to see if gauge reads
above 17 in. of Hg vacuum;
(viii) Record starting time, cassette number, and sampler
number;
(ix) At end of sampling period stop pump and record time;
and
(x) Controls with each batch of samples collected, two additional
filter cassettes should be subjected to exactly the same handling
as the samples, except that they are not opened. These control
filters should be weighed in the same manner as the sample
filters.
Any difference in weight in the control filters would indicate
that the procedure for handling sample filters may not be
adequate and should be evaluated to ascertain the cause of
the difference, whether and what necessary corrections must
be made, and whether additional samples must be collected.
(d) Shipping. The cassette with samples should be collected,
along with the appropriate number of blanks, and shipped to
the analytical laboratory in a suitable container to prevent
damage in transit.
(e) Weighing of the sample should be achieved as follows:
(i) Remove shrink band;
(ii) Remove top and middle sections of cassette and bottom
plug;
(iii) Remove filter from cassette and weigh to an accuracy
of 10 æg; and
(iv) Record weight in log against original weight.
(f) Calculation of volume of air sampled should be determined
as follows:
(i) From starting and stopping times of sampling period,
determine length of time in minutes of sampling period; and
(ii) Multiply sampling time in minutes by flow rate of critical
orifice in liters per minute and divide by 1000 to find air
quantity in cubic meters.
(g) Calculation of dust concentrations should be made as follows:
(i) Subtract weight of clean filter from dirty filter and
apply control correction to find actual weight of sample.
Record this weight (in mg) in log; and
(ii) Divide mass of sample in mg by air volume in cubic meters
to find dust concentration in mg/m. Record in log.
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