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ESH Manual Page: 4000: Industrial Hygiene

The Sanford Underground Laboratory at Homestake (otherwise known as Sanford Lab) industrial hygiene policy requires that all operations at the laboratory be performed in a safe, responsible, and compliant manner.  This includes maintaining personnel exposure to chemical, physical, and biological agents within acceptable exposure limits.  This policy further requires that exposures be minimized by the use of hazard elimination, engineering controls, personal protective equipment, and administrative controls.


This chapter provides requirements and guidance related to select industrial hygiene concerns, hazards, and controls.  Industrial Hygiene issues covered in this policy include:  drinking water, non-ionizing radiation, radon, noise, ventilation, hoods, HEPA filters, biohazards, chemicals, asbestos, confined spaces, lead, chromium VI, respirators, heat stress, and illumination.  It applies to all Sanford Laboratory employees, scientist, contractors, and guests.


3.1. Department Directors

Department Directors are responsible for:

  • Working in conjunction with various departments to ensure engineering controls (such as hazard control ventilation) are meeting minimum performance standards and effectively preventing personnel over-exposure to chemical, physical, or biological hazards.
  • Working with the EHS Department to ensure that all employees in their department have received the proper training.
  • Ensuring areas where substances hazardous to health of employees are used have the proper warning signs displayed, in consultation with the EHS department; and
  • Including qualitative exposure assessment of chemical, physical, and biological hazards during the development and annual review of JHAs. 

3.2. EHS Department

The EHS Department is responsible for:

  • Maintaining, administering, and revising the Industrial Hygiene Policy as needed;
  • Developing and implementing industrial hygiene training;
  • Working with appropriate staff to indentify identify & control health hazards; 
  • Working with the IH/Safety Technician to establish monitoring priorities; 
  • Serving as a resource for health related questions & assistance; and
  • Periodically auditing the Industrial Hygiene Policy once every year.

3.3. IH/Safety Technician

The IH/Safety Technician is responsible for:

  • Performing or overseeing industrial hygiene surveys; 
  • Performing respirator fit tests to laboratory personnel;
  • Notifying supervisors and personnel of monitoring results; 
  • Verifying that added controls are sufficient to reduce exposure below OEL limits;
  • Recommending engineering or administrative controls to prevent personnel exposure to chemical, physical, or biological hazards; 
  • Recommending warning signs where appropriate; 
  • Maintaining industrial hygiene survey and calibration equipment; 
  • Maintaining industrial hygiene survey records, notifications of personal monitoring memos, and equipment calibration logs; 
  • Providing or coordinating hazard-specific training for personnel who work with hazardous materials or carcinogens; 
  • Reviewing plans for new operations and significant changes to ongoing operations that involve hazardous materials or carcinogens;  
  • Providing industrial hygiene oversight for contractor activities; and
  • Revising the Industrial Hygiene Policy annually. 

3.4. Laboratory Personnel

All Laboratory Personnel are responsible for: 

  • Completing required training in hazardous materials usage before working with them;
  • Receiving medical monitoring and sampling of work tasks as required;
  • Refraining from consuming food or beverages (including chewing gum) in any industrial area where chemicals are used;
  • Using hazard control ventilation and personal protective equipment provided;
  • Reporting unusual odors or suspected exposures to supervisors and/or to the EHS Department.

3.5. Project Managers

Project Managers are responsible for:

  • Reviewing proposed processes involving chemical, physical, or biological hazards with the EHS Department before installing new or moving existing equipment; 
  • Working in conjunction with various departments and the involved contractor(s) to ensure engineering controls (such as hazard control ventilation) are meeting minimum performance standards and effectively preventing personnel over-exposure to chemical, physical, or biological hazards; 
  • Reporting deficient engineering controls to the proper authority for repairs;
  • Following up on recommendations provided by the EHS department staff; 
  • Ensuring that laboratory personnel under their supervision wear any personal protective equipment (PPE) needed for the task performed;
  • Ensuring all chemicals and carcinogen containers brought onsite by the involved contractor(s) display manufacturer's warning labels or appropriate substitute labels;
  • Ensuring areas where substances hazardous to health of contractor employees are used have the proper warning signs displayed, in consultation with the EHS department; 
  • Choosing less-hazardous or non-carcinogenic materials whenever possible, in consultation with the EHS department; and
  • Including qualitative exposure assessment of chemical, physical, and biological hazards during the development and annual review of JHAs;

3.6. Supervisors

Supervisors are responsible for:

  • Reviewing proposed processes involving chemical, physical, or biological hazards with the EHS Department before installing new or moving existing equipment; 
  • Ensuring that laboratory personnel under their supervision wear any personal protective equipment (PPE) needed for the task performed;
  • Reporting deficient engineering controls to the proper authority for repairs;
  • Following up on recommendations provided by the EHS department staff; 
  • Ensuring all chemical containers display manufacturer's warning labels or appropriate substitute labels; and
  • Choosing less-hazardous or non-carcinogenic materials whenever possible, in consultation with the EHS department; 

Air sampling: The collection of samples of air followed by laboratory analysis to measure the presence and concentration of chemical, physical, or biological pollutants in the air. 

Action Level:  Unless specifically defined in regulatory standards, the action level will be defined as ½ of the Occupational Exposure Limit (OEL).  The OSHA action level for noise is defined as 85 dB.

Analytical method: A standardized laboratory procedure used to determine the amount or concentration of a certain contaminant in an air or wipe sample. 

Area air sampling: The collection of air samples from a fixed location in a work area. 

Biological hazard: Hazard from biological agents such as viruses, bacteria, spores, fungi, blood borne pathogens. 

Carcinogen: A material that causes the development of cancerous growth in living tissue. 

Chemical hazard: Hazard from chemical hazardous materials such as acids, bases, solvents, cryogens, etc. 

High-efficiency particulate air (HEPA) filter: A filter capable of removing from the air at least 99.97 percent of dust, pollen, mold, bacteria and any airborne particles with a size of 0.3 micrometers or larger. 

Industrial hygiene (IH): The science devoted to the anticipation, recognition, evaluation, prevention, and control of those occupational factors or stresses arising in or from the workplace which may cause sickness, impaired health and well being, or significant discomfort among workers or citizens of the community. 

Industrial hygiene survey: Workplace survey for hazardous materials and contaminants, often including air sampling. 

Industrial hygienist: A professional qualified by education, training, and experience to anticipate, recognize, evaluate and develop controls for occupational health hazards and environmental issues. 

Hazard control ventilation: An industrial exhaust system that captures and removes contaminants emitted from local sources before dilution into ambient workplace air can occur; includes chemical fume hoods, soldering bench hoods, extractor arms, glove boxes, and biological safety hoods or cabinets. 

Medical surveillance: Periodic medical evaluation for personnel potentially exposed to designated chemical, biological, and physical hazards. 

Occupational exposure limit (OEL): An exposure limit that is the lower of the permissible exposure limit or threshold limit value (see permissible exposure limit or threshold limit value). 

Occupational Safety and Health Administration (OSHA): Regulatory agency under the United States Department of Labor created by Congress to ensure safe and healthful working conditions for working men and women by setting and enforcing standards and by providing training, outreach, education and assistance.

Permissible exposure limit (PEL): An exposure limit published and enforced by the federal Occupational Health and Safety Administration (OSHA) as a legal standard. PEL may be either a time-weighted-average (TWA) exposure limit (eight hour), a 15-minute short term exposure limit (STEL), a ceiling (C), and may have a skin designation. 

Personal air sampling: The collection of air samples at the worker's breathing zone to reflect the level of a worker's exposure to a contaminant throughout a work day. 

Personal noise sampling: The collection of noise samples at the worker's hearing zone to reflect the level of a worker's exposure throughout a work day. 

Physical hazard: Hazard from physical agents such as noise, non-ionizing radiation, and magnetic fields. 

Threshold limit value (TLV): Recommended guidelines for occupational exposure to airborne contaminants published by the American Conference of Governmental Industrial Hygienists (ACGIH). TLVs represent the average concentration for an eight-hour workday and a 40-hour workweek to which nearly all workers may be repeatedly exposed without adverse effect. 

Wipe sampling: A procedure to check for contaminants by wiping a representative surface of known area with an acceptable wipe material, which is analyzed by chemical extraction.


5.1. Drinking Water
5.1.1. General

Most drinking water hazards fall within a few common areas.  Some drinking-fountain units and copper-pipe dead legs (dead-end pipes) that are not flushed or used frequently can produce copper contamination in excess of allowable levels.  Rust from iron piping is observed in some older facilities.  Occasionally, other various off-colors and tastes are reported.  When designing/installing potable water systems that supply chemical-containing systems, it is important to install adequate backflow devices that prevent back-siphoning of toxic materials into the potable water system.  Hoses extending into sinks are a common potential problem, if backflow devices are not installed.  All potable water sources onsite shall comply with the following OSHA sanitation standards in 29 CFR 1910.141(b) (1) and 29 CFR 1926.51(a):

  • An adequate supply of water shall be available at all places of employment.
  • Portable drinking water dispensers shall be designed, constructed, and serviced so that sanitary conditions are maintained, shall be capable of being closed, and shall be equipped with a tap. 
  • Open containers such as barrels, pails, or tanks for drinking water from which the water must be dipped or poured, whether or not they are fitted with a cover, are prohibited.
  • Any container used to distribute drinking water shall be clearly marked as to the nature of its contents and not used for any other purpose.
  • The common drinking cup is prohibited. Where single service cups (to be used but once) are supplied, both a sanitary container for the unused cups and a receptacle for disposing of the used cups shall be provided.

5.1.2. Additional Information

Contact the EHS Department for the following:

  • Concerns regarding drinking-water quality. Sampling of the water for contamination may be warranted, depending on the specific situation.

5.2. Non-Ionizing Radiation

Non-Ionizing Radiation (NIR) refers to electromagnetic radiation with insufficient energy to release a bound electron from an atom.  NIR includes the following categories of radiation:  ultraviolet (UV), visible light, infrared, radio frequency, microwave, magnetic fields, and lasers.

5.2.1. Exposure Limits

Exposures to non-ionizing radiation must be maintained below the limits specified in Threshold Limit Values for Physical Agents, American Conference of Governmental Industrial Hygienists (ACGIH).  Additional information and requirements for lasers are provided in the Lasers policy (under development).

5.2.2. Methods of Exposure Control

Exposures to non-ionizing radiation must be limited by engineering controls when feasible, followed by administrative controls and personal protective equipment.  Access must be limited to authorized personnel only whenever the whole body could enter magnetic field strength exceeding 5 Gauss.  Delineating the 5 Gauss line and posting magnetic field warning signs are generally acceptable access control.

5.2.3. Additional Information

Contact the EHS Department for the following:

  • Assistance with NIR.
  • Information about the Laser policy (under development)

5.3. Radon

5.3.1. General

Radon is a naturally-occurring, colorless, odorless, tasteless, radioactive gas. It is formed from the natural radioactive decay of uranium and thorium found in rocks, soil, and water. Radon is considered a known human carcinogen that has the potential to cause lung cancer in humans.  Generally, where radon concentrations disperse into the open environment and are not "artificially enhanced," exposures are likely below any exposure limits.  However, where radon concentrations are confined, enclosed, or restricted within a space, such as the underground laboratory, their containment may artificially enhance or increase the radon concentration level.

5.3.2. Recognition, Monitoring, and Control 

Sanford Lab performs continuous monitoring at strategic places on multiple underground levels.  Workplaces are evaluated for proper ventilation that will reduce possible exposures.  An exposure limit of 30 picoCuries per liter (pCi/L) over a 40 hr work week is used as a threshold limit to trigger additional controls to a work area if needed.  All monitoring results and additional controls are reviewed by the EHS Department.

5.3.3. Additional Information

Contact the EHS department for the following:

  • Assistance with determining potential sources of exposure.
  • Assistance in developing options to control exposures.
  • Any additional information on radon.

5.4. Noise

Noise levels that can cause interference with verbal communication when people are only a few feet away from each other may be high enough to produce a risk to hearing.  Information on noise exposure limits, noise monitoring, and control methods to prevent overexposures to noise are found in the Sanford Lab Hearing Conservation policy. 

5.5. Ventilation, Hoods, and HEPA Filters 

 5.5.1. Underground Ventilation

Adequate ventilation is required in all work areas, including all underground work areas.  The ventilation system for underground work areas consists of the following:

  • Ross and Yates shafts area used as air inlets;
  • Oro Hondo and/or 5 Shaft are equipped with exhaust fans and are used to exhaust air from the underground.
  • A selected area known as the “ventilation footprint” has been predetermined, and sealed to prevent air flow leaks from the system.

Detailed information is available in the Ventilation Policy (under development).

5.5.2. Hoods and Local Exhaust Points

Local exhaust ventilation hoods and points are required for many operations to ensure reduction of airborne concentrations of contaminants that could pose risk to employees.  Hoods include, for example, laboratory fume hoods, soldering bench hoods, extractor arms, glove boxes, and other exhausted equipment enclosures that perform a safety or health function.

EHS establishes minimum standards of performance for each hood or system based upon code requirements, nationally recognized standards.  The performance standard for each hood is documented.  If a hood fails to meet the minimum performance standard then it is considered deficient.  If a deficient hood cannot be safely used by making an administrative modification to its use during the time it takes to be repaired then it must be taken out of service.  The responsible supervisor must ensure that a deficient hood is fixed, and to use the hood within its safety limits until it is fixed.

5.5.3. HEPA Filters

High Efficiency Particulate Air (HEPA) filters may be used to filter hazardous chemical, biological, or radioactive particles from air streams with an efficiency of 99.97%.  HEPA filters used for safety at the lab can be found in vacuum cleaners used to clean up dust and debris that contain asbestos, lead, or other particulates; biological safety cabinets in which bio-hazardous materials are handled; and in-place ventilation exhaust systems connected to lab hoods and glove boxes where radionuclides are used.

5.5.4. System Design, Installation, and Testing

New systems for contaminant control including local exhaust ventilation systems, hoods, and in-place filters must meet the requirements of any applicable state and local codes.  In addition, applicable industry standards must be consulted for guidance.  These standards include those promulgated by American Conference of Governmental Industrial Hygienists, American Society of Heating, Refrigerating, and Air-Conditioning Engineers, American Industrial Hygiene Association, and American National Standards Institute.  The EHS Department may be consulted to serve as a resource in determining the applicable design, construction, and performance standards applicable to a project.  Responsibility for assuring code compliance and conformance with applicable standards rests as follows:

  • For projects executed by facility operations, the Operations Department Supervisor is responsible.
  • For projects not executed outside of facility operations, the Project Manager responsible for the activity is responsible.

New or relocated fume hoods and gas cabinets must be provided with electronic flow meters to indicate the velocity of air flowing into the hood, and to alarm when the velocity falls outside of permissible range.  Other new or relocated exhaust systems used for contaminant control must have a visible means of indicating that the system is operating properly such as a pressure gauge or manometer.  These indicators are to enable the user to determine if the system is operating properly and are in addition to any
monitoring devices installed as part of building operations.  New fume hood systems, including those involving fume hoods relocated from another location, must be tested in accordance with applicable tests contained in ASHRAE 110-1995 as a condition of acceptance.  This testing is performed by a third party, must be validated (generally by witnessing) by the appropriate Department Supervisor or Project Manager, and the results communicated to the EHS Department.  New systems may not be used for contaminant control until their installation and performance has been evaluated and verified to meet applicable standards established by the EHS Department and they have been “tagged” as such.

5.5.5. Maintenance and Inspections

The EHS department conducts periodic surveys of the performance of contaminant-control systems on the following schedule:

  • Laboratory fume hoods have electronic flow monitors that continuously indicate the velocity of air flowing into the hood.  The calibrations of these monitors are checked on a nominal one-year (radiation-use hoods) or nominal two-year (all other laboratory fume hoods) rotation.
  • Biological safety cabinets used for personnel protection are certified by an external vendor on a nominal one-year rotation.  The EHS Department verifies that the certifications have been performed by checking that the certification sticker is current.
  • Other contaminant-control ventilation systems, including those with in-place filters, are surveyed for proper operation on a nominal two-year rotation.  Filters may be checked and replaced on a more frequent basis based on maintenance procedures for each specific hood.
  • Non-specific systems such as general laboratory or shop exhaust, equipment (e.g., vacuum pump) exhaust, mechanical room exhaust, and the like are maintained by the Operations Department, and are not surveyed by EHS.

Surveys are scheduled so that all hoods in a given building are due on the first day of a particular month, and are past due three months after that date.

Documentation of all calibration, certification, and other checks are maintained by the EHS Department.  Additionally, most systems have stickers on them that indicate when the last check was performed.  The EHS Department is available to provide assistance and to monitor ventilation system progress, but the responsibility and expense for testing these systems belong to the research program.

5.5.6. Additional Information

Contact the EHS Department for the following:

  • Information on the Ventilation Policy (under development)
  • Performance evaluations of local exhaust systems
  • Information about testing HEPA filtering systems

5.6. Chemicals 

All work with chemicals will be conducted in a responsible manner that protects workers.  The Sanford Lab’s chemical hygiene and safety guidelines and requirements are contained in two
sources.  The Chemical Hygiene and Safety Plan (CHSP, under development) relates to chemical use in specific laboratory settings, and The Hazard Communication Policy (also known as the HazCom Policy, under development) addresses chemical use for other Sanford Lab locations.  Information on requirements, including chemical inventory, may be found in these documents.

5.7. Asbestos 

Asbestos is a well known health hazard, and as such, must be handled with care.   Some of the older buildings on site may contain significant amounts of asbestos, while the new construction contains minimal amounts. Examples of construction materials in the lab facilities that frequently contain asbestos include:  pipe insulation, ceiling tiles or spray-on insulation, taping compound on gypsum wallboard, floor tiles and mastic, roofing material, and transite wallboard. Information about the required recognition, monitoring, handling, and control of asbestos-related hazards are included in the Asbestos Management Plan (under development).  The Plan contains elements that are specifically required by laws and regulations, and additional requirements necessary to safely and effectively manage asbestos at the Sanford Lab.

5.8. Permit-Required Confined Spaces 

Unless proper steps are taking, working in confined spaces often exposes an employee to unacceptable hazards.  A confined space is considered “Permit Required” if it  
has one or more of the following characteristics: contains or has the potential to contain a hazardous atmosphere; contains a material that has the potential to engulf an entrant; has walls that converge inward or floors that slope downward and taper into a smaller area which could trap or asphyxiate an entrant; or contains any other recognized safety or health hazard. The Laboratory’s policy for confined space entry is outlined in Confined Spaces (EHS-7003-L1-01).

5.9. Lead (Pb)

Lead exists at the Sanford Lab in various forms and processes that present a potential employee exposure hazard.  Deteriorating lead-based paint, dust from lead shielding, and research processes using lead are potential exposure sources.  Employees may also be exposed to lead when construction, alteration, repair, renovation, painting, or decorating is done from the sanding, grinding, welding, removal, or disturbing of wall or surface materials that contain, or are coated, with lead.  Lead exposure may also occur with installation of products containing lead. Information about the required recognition, monitoring, handling, and control of lead-related hazards are included in the Lead (Pb) Program (under revision).

5.10. Chromium VI

5.10.1. General

Chromium VI compounds, often called hexavalent chromium, exist in several forms. Overexposure to chromium VI can cause irritation to the lining of the nose, nose ulcers, runny nose, and breathing problems, such as asthma, cough, shortness of breath, or wheezing in short term exposures.  The Department of Health and Human Services (DHHS), the International Agency for Research on Cancer (IARC), and the EPA have determined that chromium (VI) compounds are known human carcinogens.

5.10.2. Recognition, Monitoring, and Control

Industrial uses of hexavalent chromium compounds include chromate pigments in dyes, paints, inks, and plastics; chromates added as anticorrosive agents to paints, primers, and other surface coatings; and chromic acid electroplated onto metal parts to provide a decorative or protective coating. Hexavalent chromium can also be formed when
performing "hot work" such as welding on stainless steel or melting chromium metal. In these situations the chromium is not originally hexavalent, but the high temperatures involved in the process result in oxidation that converts the chromium to a hexavalent state.  Sanford Lab uses the OSHA Chromium VI standard for General Industry (29 CFR 1910.1026) for requirements on exposure limits, controls, and monitoring schedules.

Sanford Lab is committed to reduce any possible hexavalent chromium exposures exceeding both the OSHA action level, defined as 2.5 ug/m3, and the OSHA permissible exposure limit (PEL) of 5 ug/m3.  Any overexposure to either limits requires both controls implemented and follow-up periodic monitoring performed. Initial periodic monitoring as well as any periodic monitoring needed will be performed throughout Sanford Lab by the IH/Safety Technician in consultation with the EHS Department in determining possible areas of exposure. Monitoring will be performed according to the OSHA ID-215 analytical method or a comparable analytical method by a lab with an accreditation from the American Industrial Hygiene Association (AIHA). 

Each Department Supervisor and Project Manager will arrange for the proper controls needed for the workplaces under their authority.  Engineering controls are preferred, followed by administrative controls with personal protective equipment (PPE) used as a last resort.  The EHS Department will be available as a resource for control options and both initial & follow up monitoring.

5.10.3. Additional Information

Contact the EHS department for the following:

  • Assistance with determining potential sources of exposure.
  • Assistance in developing options to control exposures.
  • Any additional information on chromium VI.

5.11. Biological Hazards

5.11.1. General

Biological hazards include bacteria, viruses, fungi, other microorganisms and their associated toxins. They have the ability to adversely affect human health in a variety of ways, ranging from relatively mild, allergic reactions to serious medical conditions, even death. Currently, two major sources of biological exposure exist:

  • Organisms in the workplace environment – organisms found in water, soil, plants, and animals. Because many microbes reproduce rapidly and require minimal resources for survival, they are a potential danger in a wide variety of occupational settings.  Microbial organisms can be found at Sanford Lab as naturally occurring in soil & water, and as elevated growths on older, previously wet materials on both the surface and underground; and
  • • Bloodborne pathogen exposure – responders to a medical emergency may be exposed to contact with human body fluids, including bloodborne pathogens. 

5.11.2. Biological Safety

The Sanford Lab has developed the Biosafety Policy (under development) to assure conformance with federal, state, and local requirements.  Handling of microbial organisms and/or bloodborne pathogens must be in conformance with this policy.  This policy contains elements that are specifically required by laws and regulations, and
additional requirements necessary to safely and effectively manage biological hazards at the Sanford Lab.

5.11.3. Additional Information

Contact the EHS Department for the following information:

  • Information about the Biosafety Policy (under development)
  • Assistance with determining potential sources of exposure.
  • Assistance in developing options to control exposures.
  • Any additional information on biological hazards.

5.12. Respiratory Protection

The Sanford Lab uses respirators in conformance with OSHA 1910.134, 1926.103, and ANSI 88.2.  The use of respirators can help ensure that all affected individuals are protected from exposure to respiratory hazards that may be present in the workplace.  

Respirators are the last resort for control of exposures and are to be used when engineering controls, process modification, and other measures are not practical or have proved inadequate. Further information and requirements are included in the Respiratory Protection Program (under development).

5.13. Heat Stress

5.13.1. General

Heat stress, the physical stress of hot environments, can be influenced by a combination of factors, such as the type of clothing you wear, physical activity, time spent working, breaks between work activity, medications you may be taking, and environmental factors such as ambient air temperature, air velocity, and relative humidity.  There may be brief periods of hot weather that can lead to uncomfortable working conditions, and possibly, heat stress for laboratory personnel on the surface.  In addition, heat and humidity may intensify in the deep regions of the underground lab.  A mild or moderate heat stress (i.e., office environments) may cause discomfort, but it is rarely harmful to health.  However, as the heat stress approaches human tolerance limits (e.g., exterior work on hot days), the risk of heat-related disorders increases.  This section is intended to provide guidance to supervisors and workers on how to recognize and control heat stress in office environments or while working outdoors.

5.13.2. Recognizing Heat Stress

Laboratory personnel heat complaints provide good cues for the recognition of heat stress in the workplace.  Supervisors are encouraged to obtain feedback from employees on their working conditions during periods of hot weather.  Methods for obtaining this input may include visiting assigned spaces, calling employees in areas known to be warm, or questioning employees during safety and group meetings.  For additional information and training on heat stress and other outdoor hazards, contact the EHS Department.

5.13.3. Heat-Related Disorders

Heat-related disorders can be caused by prolonged periods of heat stress.  Listed below are some common heat-related disorders, including their symptoms.

A. Heat Exhaustion

Heat exhaustion occurs when your body’s ability to regulate body temperature is overwhelmed but not completely broken down.

  • Clammy, cool, moist, and pale skin
  • Fatigue and weakness
  • Heavy perspiration
  • Intense thirst from dehydration
  • Low to normal blood pressure
  • Anxiety or agitation
  • Clouded senses or impaired judgment
  • Fainting or loss of coordination
  • Loss of appetite
  • Nausea or vomiting
  • Rapid breathing
  • Slightly low oral temperature

Immediate Response Actions for Heat Exhaustion:

  • Call 911 immediately (surface) or Contact the hoist operator (underground).
  • Move the victim into the shade or a cooler area.
  • Loosen the victim’s clothing and shoes for evaporative cooling.
  • Fan the victim.
  • Elevate the victim’s legs.
  • Give the victim water.
  • Cool the victim with damp, cool towels.
  • Stay until medical help arrives.

B. Heat Stroke

Heat stroke is the most severe of the heat-related disorders.  Heat stroke is a life-threatening emergency that requires immediate medical attention.  Heat stroke is more likely to occur in outdoor work.

  • No perspiration on skin
  • Hot, red, or flushed skin
  • High body temperature, 105° or above
  • Rapid pulse
  • Difficulty breathing
  • Constricted pupils
  • High blood pressure
  • Headache or dizziness
  • Confusion or disorientation
  • Weakness
  • Nausea or vomiting
  • Seizures

Immediate Response Actions for Heat Stroke:

  • Call 911 immediately (surface) or Contact the hoist operator (underground).
  • The victim’s body temperature must be lowered as quickly as possible.  Applying damp, cool towels, or ice packs to armpits, elbows, wrists, or backs of knees may help.
  • Stay with the victim until medical help arrives.

5.13.4. Control of Heat Stress

Self-awareness is one of the key steps to reducing heat-related disorders.  Employees and supervisors should terminate exposure to heat stress at the onset of the first symptoms.  Supervisors should consider a worker’s physical condition when determining heat stress conditions.  Obesity, lack of conditioning, medical conditions, use of medications, pregnancy, and inadequate rest can increase susceptibility to heat stress even in indoor office environments.  Additional industrial hygiene practices and administrative and engineering controls are listed below.

  1. Wear lightweight, light colored, loose clothing that allows free movement of cool air over the skin’s surface to allow the removal of heat from the body by evaporation.  Evaporation of sweat from the skin is the body’s predominant heat removal system.
  2. Drink plenty of chilled hydrating fluids such as water or commercial hydrating fluids to prevent dehydration.  Since thirst is not a sufficient indicator of fluid replacement, workers are encouraged to drink about 1 cup of cool water every 15 to 20 minutes during heat stress conditions.
  3. To increase evaporation and cooling of the skin, use general ventilation or fans for spot cooling.
  4. Work demands should be made lighter by taking frequent breaks in a cooler area, completing them over a longer time period, and setting the work pace with the least heat-tolerant worker in mind.
  5. Heavy workloads should be scheduled during cooler times of the day (i.e., early morning).
  6. Wearing personal protective equipment (PPE) during hot weather can dramatically increase an individual’s heat stress level.  Non-breathable fabrics like Tyvek do not allow for the evaporation of sweat.  The use of respirators also adds an additional physiological burden, increasing heat stress levels.  Tasks requiring these types of PPE should be postponed when feasible.  If the work must be performed, then an effective work-rest cycle must be established.  The EHS Department must be contacted prior to beginning this type of work.
  7. A light, cool lunch is recommended during hot days, instead of a heavy meal.  Heavy meals can reduce your ability to release heat because your blood flow is redirected to your stomach instead of your skin for cooling.
  8. Employees should report to their immediate supervisor if they feel they are suffering from the onset of a heat-related disorder.  In emergency situations, contact Emergency Medical Services (EMS) by calling 911.

5.13.5. Screening Threshold

The table below is used as a screening tool by health and safety professionals to22.5 determine the environmental contribution to heat stress in outdoor environments.  The temperatures listed in this table take into consideration air temperature, radiant heat, and humidity (web bulb globe temperature [WBGT] Index °C).  The EHS Department is available to measure WBGT; however, when indoor air temperatures exceed 85° F (29.5°C), supervisors are responsible for exercising their judgment in modifying their employees’ work schedules, workloads, etc.


Acclimatized Worker
(WBGT values in ?C)

Un-acclimatized workder

Work Demand* Light Moderate HeavY Very HeavY LIGHT MODERATE HEAVY

Very heavy

100% work 29.5 27.5 26   27.5 25 22.5  
75% work 25% Rest 30.5 28.5 27.5   29 26.5 24.5  

50% work 50% rest

31.5 28.5 28.5 27.5 30 28 26.5 25
25% work 75% rest 32.5 31 30 29.5 31 29 28 26.5
*Work demand examples: Light – Sitting with moderate arm and leg movements. Moderate – Walking about with moderate lifting or pushing. Heavy – Heavy assembly work on a non-continuous basis. Very heavy – Shoveling wet sand.

When interior temperatures fall outside the recommended guidance range of 65°F to 85°F, department management and supervisors should use their discretion in modifying employee work assignments, including changes in location, changes in time of beginning or end of work day, sharing duties, etc.  Supervisors should consider employee medical and physical conditions when applying this temperature range as a guideline.

For employees working outside, modifications to employee work assignments should be considered when the ambient temperature exceeds 85°F.  More frequent rest periods may be required in addition to the strategies listed above.  Consideration must also be given to the increased heat stress levels caused by wearing certain types of person protective equipment (PPE).

If the temperature extremes effectively prevent an employee from performing his or her work, and alternate assignments and on-site work locations appropriate to the employee’s job classification are not available, supervisors should use their judgment in allowing their affected employees to work at home for the period during which the employee’s work cannot be performed on site.  The EHS Department neither requires nor authorizes changes in employee work assignments under extreme temperature conditions; these decisions rest with line management.

5.13.6. Additional Information

Contact the EHS Department for the following:

  • Information about heat stress
  • Information about temperature extremes in indoor environments

5.14. Illumination

5.14.1. General

Injuries due to poor workplace lighting happen often, and in a variety of workplaces and situations. Illnesses such as eye strain and severe headaches are also attributed to poor or wrong lighting. Poor lighting may also conceal additional hazards, including uneven or slippery surfaces, moving equipment, and improperly guarded electrical or mechanical components.  Specific underground hazards such as poor ground conditions and open holes may also be concealed by improper lighting. 

5.14.2. Recognition, Monitoring, and Control

Several factors should be considered in determining the amount of lighting needed:

  • The nature of the work;
  • work environment;
  • daytime and nighttime lighting needs; 
  • glare or reflections due to other lights or outdoor light; and
  • Any specific hazardous situations.

Adequate general lighting is required in workplaces, including the access to/from these workplaces.  Table 4.13A shows the workplace requirements for lighting that have been developed under the OSHA 29 CFR 1926 Construction Standard: 

Table 5.13.A: Workplace Lighting Requirements

Required Footcandles 

Area of Operation 

General construction area lighting. 

General construction areas, concrete placement, excavation and waste areas, access ways, active storage areas, loading platforms, refueling, and field maintenance areas. 

Indoors: warehouses, corridors, hallways, and exitways. 

Tunnels, shafts, and general underground work areas: (Exception: minimum of 10 foot-candles is required at tunnel and shaft heading during drilling, mucking, and scaling. Bureau of Mines approved cap lights shall be acceptable for use in the tunnel heading) 


General construction plant and shops (e.g., batch plants, screening plants, mechanical and 

electrical equipment rooms, carpenter shops, 

rigging lofts and active store rooms, mess halls, and indoor toilets and workrooms.) 


First aid stations, infirmaries, and offices. 

 Periodic monitoring will be performed throughout Sanford Lab by the EHS Department to ensure compliance with the above table.

Each Department Supervisor and Project Manager will arrange for increased lighting for the workplaces under their authority.  The EHS Department will be available as a resource for control options and follow up monitoring.

5.14.3.  Additional Information

Contact the EHS department for the following:

  • Assistance with determining if light levels are sufficient.
  • Assistance in developing options to increase lighting.

6.1. References

  • American National Standards Institute (ANSI), ANSI/AIHA Z9.5-1995, American National Standard for Laboratory Ventilation
  • American National Standards Institute (ANSI) Z88.2, Practices for Respiratory Protection
  • Industrial Ventilation, a Manual of Recommended Practice, American Conference of Governmental Industrial Hygienists, 1995

6.2. Standards

  • 29 CFR 1910 Occupational Safety and Health Standards for General Industry (29 CFR 1910) and 29 CFR 1926 Construction
  • 29 U.S.C. 668 et seq., Occupational Safety and Health Act (asbestos)
  • 40 CFR 61, Subpart M, National Emission Standard for Asbestos, and Subpart F, Appendix A
  • 40 CFR 141, 142, 143, EPA Primary and Secondary Drinking Water Standards
  • 40 CFR 170, 171 Subpart E, Pesticide Programs
  • Center for Disease Control (CDC) and National Institutes of health (NIH), Biosafety in Microbiological and Biomedical Laboratories, and 3rd Edition.
  • Guidelines for Research Involving Recombinant DNA Molecules, National Institutes of Health (NIH), Federal Register, March 12, 1996 (61 FR 10004).
  • Flammable and Combustible Liquids Code, National Fire Protection Association, NFPA 30
  • Threshold Limit Values for Chemical and Physical Agents, American Conference of Governmental Industrial Hygienists (ACGIH)

6.3. Related Documents

  • Asbestos Management Plan (to be developed)
  • Chemical Hygiene and Safety Plan (CHSP) (to be developed)
  • Confined Spaces
  • Hearing Conservation
  • Lead (Pb) Program
  • Respiratory Protection Program
  • Ventilation Policy (to be developed)