SDS Wood Ash

Safety Data Sheet Hardwood Ash


1. Product Identification

Synonyms: Biomass Fuel Ash, Wood Boiler Ash, Wood Fly Ash

2. Hazardous Ingredients/Identity Information





Exposure Limits


Fly Ash, as Particulate Not Otherwise Regulated (PNOR, PNOS)A


1 43


5 mg/m3 15 mg/m3 3 mg/m3 10 mg/m3

Respirable fraction - PNOR Total particulate - PNOR Respirable fraction - PNOS Inhalable fraction - PNOS

Calcium carbonate1 (CaCO3)


45 66


15 mg/m3 5 mg/m3 3 mg/m3 10 mg/m3

Total particulate - PNOR Respirable fraction - PNOR Respirable fraction - PNOS Inhalable fraction - PNOS

Potassium carbonate2 (K2CO3)




None None

Aluminum oxide3 (Al2O3)


<1 5


5 mg/m3 15 mg/m3 1mg/m3

Respirable fraction Total particulate Respirable fraction

Iron oxide4


<1 1


10 mg/m3 5 mg/m3

As iron oxide fume Dust & fume, as Fe

Magnesium oxide5 (MgO)


1.6 2.9


15 mg/m3 10 mg/m3

Total particulate Inhalable fraction

Manganese (Mn)




5 mg/m3 0.2 mg/m3

Ceiling None

1Limestone; 2potash; 3alumina; 4ferric oxide; 5.magnesia
A The use of a PNOR or PNOS exposure limit should only be applied in the absence of other compounds with lower exposure limits and the criteria for PNOR (OSHA) or PNOS (ACGIH) should be consulted.

3. Hazard Identification

Primary Health Hazards: Fly Ash can cause respiratory tract irritation, skin irritation and eye irritation. Appearance and Odor: Fly ash is a solid, grey/black or black/tan odorless powder which may contain

solidified masses. It is the residual from the burning of a combination of carbonaceous materials.

3. Hazard Identification (cont’d.)

Primary Route(s) of Exposure:

Skin: Dust Inhalation: Dust Eye: Dust

Eye Contact: Exposure to airborne fly ash or ash dust may cause immediate or delayed irritation or inflammation. As the material becomes wet, it will become corrosive and cause burning of the eyes. Skin Contact: Fly ash may cause dry skin, discomfort and irritation in susceptible individuals. Once wet, the material becomes corrosive and will cause burning of the skin.

Skin Absorption: Not known to occur under normal use.

Inhalation (acute): A singe, short-term exposure to the dry powder presents little or no hazard. High 
concentrations of fly ash may cause unpleasant obstruction to the nasal passages and minor chemical irritation to the membranes of the upper respiratory tract. Fly ash deposition in the nasal passages may lead to nosebleed and/or headache.

Inhalation (chronic): The risk of injury depends on the duration level of exposure and make up of the ash but may cause dermatitis and lung irritation.

Ingestion: Do not ingest ash. Although ingestion of small quantities of ash is not known to be harmful, large quantities can cause distress to the digestive tract.

Medical Conditions Generally Aggravated by Exposure: Respiratory, skin and eye disorders; blood system disorders, liver disorders, iron metabolic disorders, nervous system disorders. Individuals with history of prior lung disease (e.g., bronchitis, emphysema or chronic obstructive pulmonary disease [COPD] who inhale fly ash may report an aggravation of these conditions.

Carcinogenicity Listing: This particular fly ash is not listed as a carcinogen by IARC or NTPit does not contain crystalline silica.

IARC Monographs: OSHA Regulated:

4. Emergency and First-Aid Procedures

Ingestion: Not a typical exposure route. Should a significant amount of ash be ingested, refer to a physician.

Eye Contact: Fly ash will cause mechanical and chemical irritation. Treat dust in the eyes as a foreign object. Flush with water for 15 minutes, including under the lids to remove dust particles. Flush eyes immediately with copious amount of water to remove particles. Seek medical attention for irritation or abrasions.

Skin Contact: Fly ash may cause drying or mechanical abrasion of the skin upon repeated contact. Wash exposed skin with cool water and pH-neutral soap. If the ash becomes wet, it will become corrosive and cause burning of skin. Get medical help if rash, irritation or dermatitis occurs. Barrier cream may protect the skin from drying and provide some protection against corrosivity. Promptly remove and launder clothing that is dusty or wet with ash. Thoroughly wash skin after exposure to dust or wet ash.

Skin Absorption: Not known to occur with normal use.
Inhalation: High concentrations of fly ash may cause unpleasant obstruction to the nasal passages and minor chemical irritation to the membranes of the upper respiratory tract. Fly ash deposition in the nasal passages may lead to nosebleed and/or headache. Remove to fresh air. Get medical help if persistent irritation, severe coughing, or breathing difficulty occurs.

Note to Physician: None.

5. Fire and Explosion Data

Flash Point (Method Used): NAP
Flammable Limits: LEL = NAP UEL = NAV Extinguishing Media: Use sand, fine water mist or fog spray on smoldering fly ash.
Autoignition Temperature: 450° 5,000°F, (232° 2760°C) depending upon the degree of

incompletely combusted organic material in the ash.
Special Firefighting Procedures: Avoid using a high-pressure stream of water directed at smoldering fly ash. This may cause a flare up or explosion.
Unusual Fire and Explosion Hazards: Depending on moisture content, and more importantly, particle diameter and airborne concentration, fly ash in a contained area may explode in the presence of an ignition source. Fly ash may similarly deflagrate (combustion without detonation like an explosion) if ignited in an open or loosely contained area. Completely combusted (pure) fly ash is expected to have an extremely low potential for explosion, even under typical dust explosion conditions (i.e., high airborne concentrations in the presence of an ignition source). However, fly ash containing some degree of incompletely combusted matter (as low as 7 % in some instances) is expected to present the potential for explosion when a high airborne dust concentration comes in contact with an ignition source. The LEL for this fly ash product is an unknown variable and is dependent upon the degree of incompletely combusted organic material in the product. Use good housekeeping to prevent accumulations of material. Avoid conditions that generate significant quantities of airborne dust.

HMIS Rating (Scale 0-4): Health = 2 Fire = 1 Physical Hazard= 0 NFPA Rating (Scale 0-4): Health = 2 Fire = 1 Reactivity = 0

6. Accidental Release Measures

Steps to be Taken In Case Material Is Released or Spilled: Fly ash may be vacuumed or shoveled after wetting for recovery or disposal. Avoid generating dusty conditions and provide good ventilation. Use NIOSH approved filtering facepiece respirator (“dust mask”) in accordance with regulatory requirements if exposure limits are exceeded or if discomfort is experienced.

7. Handling and Storage

Precautions to be Taken In Handling and Storage: When wet, fly ash will become corrosive (pH > 13). Use proper personal protective equipment (gloves and goggles) when handling. Loading and unloading fly ash may generate excessive airborne ash dust. Barrier cream may protect the skin from drying and provide some protection against corrosivity. Use a NIOSH-approved filtering facepiece respirator (“dust mask”) and dust goggles when recommended allowable exposure limits may be exceeded. Keep bulk and bagged ash dry until used. Stack bagged material in a secure manner to prevent falling. Bagged ash is heavy and poses risks such as sprains and strains to the back, arms, shoulders and legs during lifting and mixing. Handle with care and use appropriate control measures. This product may present an engulfment hazard. To prevent burial or suffocation, do not enter a confined space such as a silo, bin, bulk truck, or other storage container or vessel that stores or contains ash. Ash can build up or adhere to the walls of a confined space. The ash can release, collapse or fall unexpectedly. Areas of accumulated fly ash may retain heat for extended periods of time. Use caution when stepping into deep accumulations. Fly ash should be stored and transported to the extent possible in a covered bin or container. Properly ground all pneumatic conveyance systems. The potential exists for static build-up and static discharge when moving ash through a plastic, non-conductive, or non-grounded pneumatic conveyance system. The static discharge may result in damage to equipment and or injury to workers.

8. Exposure Control Measures, Personal Protection

Personal Protective Equipment:

RESPIRATORY PROTECTION – Use NIOSH approved filtering face piece respirator (“dust mask”) or higher levels of respiratory protection as indicated for particulates if there is a potential to exceed the exposure limits or for symptom relief or worker comfort following a determination of risk.

EYE PROTECTION Goggles or safety glasses are recommended when handling this product PROTECTIVE GLOVES Cloth, canvas, or leather gloves are recommended when handling the dry product to minimize potential mechanical irritation. If product becomes wet, neoprene, butyl, or nitrile gloves are recommended.

Protective clothing with long sleeves or

disposable outer garments may be desirable in extremely dusty areas.
Dampen ash with water and carefully sweep, or vacuum areas where fly ash has settled to avoid excessive accumulation. Minimize blowdown or other practices that generate high airborne dust concentrations. The use of barrier skin cream may prevent skin irritation in susceptible individuals.


LOCAL EXHAUST Provide local exhaust as needed so that exposure limits are met. Ventilation to control dust should be considered where potential explosive concentrations and ignition sources are present. The design and operation of any exhaust system should consider the possibility of explosive concentrations of fly ash within the system. See “SPECIAL” section below.

MECHANICAL (GENERAL) Provide general ventilation in processing and storage areas so that exposure limits are met.

SPECIAL Ensure that exhaust ventilation and material transport systems involved in handling this product contain explosion relief vents or suppression systems designed and operated in accordance with applicable standards if the operating conditions justify their use.


9. Physical/Chemical Properties

Physical Description: Solid (powder) grey/black or brown/tan powder which may contain solidified masses.

Boiling Point (@ 760 mm Hg): Evaporation Rate (Butyl Acetate = 1): Freezing Point:
Melting Point:
Molecular Formula:
Molecular Weight:
Oil-water Distribution Coefficient: Odor Threshold:
Solubility in Water (% by weight): Specific Gravity (H
2O = 1):
Vapor Density (air = 1; 1 atm):
Vapor Pressure (mm Hg):
% Volatile by Volume [@ 70°F (21°C)]:

None; solid NAP
Not determined > 13
Slightly (<5%) NAP
None; solid

10. Stability and Reactivity

Stability: Unstable Stable
Conditions to Avoid: Avoid open flame
Incompatibility (Materials to Avoid): Avoid contact with oxidizing agents Hazardous Decomposition or By-Products: NAP
Hazardous Polymerization: May occur Will not occur Sensitivity to Mechanical Impact: NAP
Sensitivity to Static Discharge: NAP

11. Toxicological Information

Toxicity Data: None available for product in final form. Individual component information for ingredients listed in Section 2 is described below if available.


Calcium carbonate: Acute oral toxicity (LD50): 6450 mg/kg, Rat.
Aluminum oxide: Toxicity Data: (RTECS DATA) Inhalation Rat: lowest published toxic concentration:

200 mg/m3/5 hour/28 week - intermittent - Lung, Thorax, or Respiration.

Local Effects: Irritation of skin, eyes and the respiratory system
Magnesium oxide: No LD50/LC50 information found relating to normal routes of occupational exposure Manganese: Oral LD50 Rat: > 3478 mg/kg
Iron oxide: Toxicity Data: Oral rat LD50: greater than 10000 mg/kg
Potassium carbonate: Toxicity Data: Oral rat LD50: 1870 mg/kg.
Target Organs: Skin, eyes and respiratory system

12. Ecological Information

Environmental Fate: No information available at this time. Materials can be used as an amendment to add calcium, potassium and magnesium to the soil. USDA (1998) reported that trace levels of heavy metals were within normal ranges for plants growing on areas treated with wood fly ash.

Environmental Toxicity: No information available at this time

13. Disposal Considerations

Waste Disposal Method: Dry land disposal is acceptable and is not considered a hazardous waste in most states or provinces including Ontario. However, fly ash will become corrosive in the presence of water, due to the calcium, magnesium, and potassium content. Do not dispose in areas of high ground water or where surface runoff is adjacent to waterways. It is, however, the user’s responsibility to determine at the time of disposal whether the product meets EPA RCRA criteria for hazardous waste. Follow applicable federal, state, and local regulations.

14. Transport Information

Mode: (Air, Land, water) Not regulated as a hazardous material by the U.S. Department of Transportation. Not listed as a hazardous material in Canadian Transportation of Dangerous Goods (TDG) regulations.

Proper Shipping Name: NAP Hazard Class: NAP UN/NA ID Number: NAP Packing Group: NAP Information Reported for Product/Size: NAP

15. Regulatory Information

TSCA: Fly ash is listed on the TSCA inventory. All individual chemical components are on the TSCA inventory as well.

DSL: Fly ash is listed on the DSL inventory. All individual chemical components are on the DSL

inventory as well.
OSHA: Fly ash and all listed ingredients are considered by OSHA to be hazardous chemicals or irritants

and should be included in the employer’s hazard communication or WHMIS program.


California Proposition 65 This product does not contain any substances identified on the Proposition 65 List.

Pennsylvania This product contains aluminum oxide, iron oxide (ferric oxide), magnesium oxide and manganese, substances that are listed in Pennsylvania.

New Jersey This product contains aluminum oxide, iron oxide (ferric oxide), magnesium oxide and manganese, substances that are listed in New Jersey.

SARA 313 Information: This product contains the following substances subject to the reporting requirements of SARA Title III Section 313 and 40 C.F.R. Part 372: Aluminum Oxide only if in the fibrous form.

SARA 311/312 Hazard Category: This product has been reviewed according to the EPA "Hazard Categories" promulgated under SARA Title III Sections 311 and 312 and is considered, under applicable definitions, to meet the following categories:

An immediate (acute) health hazard Yes A delayed (chronic) health hazard Yes A corrosive hazard No A fire hazard No A reactivity hazard No A sudden release hazard No

FDA: Not intended for use as a food additive or food contact item.
WHMIS Classification: Controlled product - potassium carbonate: E (corrosive material).

16. Additional Information

User’s Responsibility: The information contained in this Safety Data Sheet is based on the experience of occupational health and safety professionals and comes from sources believed to be accurate or otherwise technically correct. It is the user’s responsibility to determine if the product is suitable for its proposed application(s) and to follow necessary safety precautions. The user has the responsibility to make sure that this SDS is the most up-to-date issue.