Outdoor Additive


Add to milk paint to create a durable exterior, all-natural paint. Outdoor Additive boasts in its ability to reduce tannin’s leaching through milk paint from wood knots and discoloring the surface. It also provides improved resistance to mold and mildew growth.

SKU: ODA Category:

Product Description


“Outdoor Additive” by The Real Milk Paint Company is a borate compound, similar to borax. Borax can be found at the grocery store as Twenty Mule Laundry Booster. It is mined from the ground mainly in California. Borax is safe and non-toxic and has multiple uses. “Outdoor Additive” is a slightly modified borax compound that is very finely milled, so that when added to the paint it remains smooth.

Real Milk Paint® with “Outdoor Additive” is suitable for exterior porous surfaces such as wood, concrete, brick, and stucco. It should not be used over existing paint. The paint would need to be removed first. Real Milk Paint® with “Outdoor Additive” will not blister and peel like modern paint but will act as a sacrificial coating that will gently wear away with time. The way paint is supposed to work.

Now Real Milk Paint® can be used on your outdoor projects. Having an old house built in 1892 with original wood clapboard siding and windows, I wanted to use a period-appropriate paint for the restoration. While milk paint does work well outdoors as is, adding “Outdoor Additive” makes the paint even more superior and is one of the best wood finishing products that you can use.

For enhanced exterior use and improved water resistance, topcoat Real Milk Paint® with Outdoor Defense Oil.


  • Tannin Stain Blocker – blocks stains from coming through the paint on woods such as cedar and knotty pine.
  • U.V. light protection – inhibits ultraviolet light from destabilizing the paint film.
  • Mold Inhibitor – inhibits mold from developing (used at the recommended level).
  • Flame Retardant – helps to control and reduce the spread of flames.
  • Bactericide – will not promote the growth of bacteria in liquid paint.


Package contains 1 cup of Outdoor Additive.

  1. Mix 1 gallon of Real Milk Paint with water as per direction on the label
  2. Add this entire container of Outdoor Additive to the Gallon of Real Milk Paint (contains 1 cup of powder)
  3. When dry, there may be some chalky look. This will wear off the paint as it weathers.

To mix smaller quantities :

  • 1/4 cup per Quart of Real Milk Paint
  • 1/8 cup per Pint of Real Milk Paint

Video Instructions

Material Safety Data Sheet

126 Commerce Dr
Hohenwald TN 38462
Phone: 215-538-3886
Fax: 215-538-3886
24 Hour Emergency Phone: Chem-Tel Inc. 800-255-3924

Emergency Telephone Numbers:
24 hrs. Chem-Tel 800-255-3924 (within continental US)
24 hrs. 813-248-0585 (collect) (outside continental US)

Updated: June 2015

B. Labs, Inc.
Revision date: 5/12/2006
Date Updated: 1/1/2012 BUSAN 11-M7
24 Hour Emergency Phone: (901) 767-2722
Irritating to eyes.
Chemical Name % by Weight TLV CAS Number
Barium metaborate monohydrate 90 TWA: 0.5 mg/m3 13701-59-2

B. Labs reports the component(s) listed above as known OSHA hazardous material(s) contained in this product.

B. Labs considers any product/component having an established exposure limit (a TLV/TWA) or containing a known carcinogen (present over 0.1%) as being an OSHA hazardous material. As listed in Section 5 Busan 11-M7 does not contain a known carcinogen but it does have an established TWA of 0.5 mg/m3.

Even though this product contains a known OSHA hazardous material this should not pose a problem because people handling this product, as described, will not be exposed to a TWA of > 0.5 mg.m3.
Eye Exposure: Flush immediately with copious amounts of tap water or normal saline (minimum of 15 minutes). Take exposed individual to a health care professional, preferably an ophthalmologist, for further evaluation.
Skin Exposure:
Wash exposed area with plenty of water. Repeat washing. Remove contaminated clothing and wash thoroughly before reuse. If irritation persists consult a health care professional.

If exposure by inhalation is suspected, immediately move exposed individual to fresh air. If individual experiences nausea, headache, dizziness, has difficulty in breathing or is cyanotic, seek a health care professional immediately.

DO NOT INDUCE VOMITING. Rinse with copious amounts of water or milk, first. Irrigate the esophagus and dilute stomach contents by slowly giving one (1) to two (2) glasses of water or milk. Avoid giving alcohol or alcohol related products. In cases where the individual is semicomatose, comatose or convulsing, DO NOT GIVE FLUIDS BY MOUTH. In case of intentional ingestion of the product seek medical assistance immediately; take individual to nearest medical facility.

1. Effects from Acute Exposure:
Eye exposure: lightly hazardous in case of eye contact (irritant).
Skin Exposure: Non-irritant for skin. Non-sensitizer for skin.

Inhalation: Slightly hazardous in case of inhalation. Effects will depend on concentration and length of time of exposure.

Ingestion: May be hazardous in case of ingestion. Effects will depend on concentration and length of time of exposure.

2. Effects from Chronic Exposure:
The effects from chronic exposure to this product have not been evaluated. Chronic ingestion of some barium compounds may have an adverse effect on the cardiovascular system.
May cause damage to the following organs: the reproductive system, cardiovascular system, upper respiratory tract, eyes.

Boron compounds have been associated with reproductive effects in animal studies.

5. Toxicological Information
Acute Effects: Acute Oral (LD50) = 850 mg/kg Male rat
Acute Oral (LD50) = 530 mg/kg Female rat

Acute Dermal (LD50) = >2000 mg/kg Rabbit

Acute Inhalation (LC50) = >2.54 mg/l (4 hours) Rat

Carcinogenic Potential: Not tested by B.Labs. Not shown as a carcinogen by OSHA, IARC, or NTP.

Irritant/Sensitization Effects: Slightly hazardous in case of eye contact (irritant).

Non-irritant for skin. Non-sensitizer for skin.

Slightly hazardous in case of inhalation. Effects will depend on concentration and length of time of exposure.

6. Environmental Toxicological Information
LC50 = 20.3 mg/l 48 hours Daphnia magna
LC50 = >151 mg/l 96 hours Bluegill sunfish
LC50 = >62 mg/l 96 hours Rainbow trout
7. Physical and Chemical Properties
Appearance: White amorphous crystalline solid
Odor: None.
Density: 3.35 g/cm3
Flash Point: Not available.
Melting/Freezing Point: Not available.
Boiling Point: Not Available.
Solubility: Very slightly soluble in cold water. Very slightly soluble in hot water.
pH (Neat) Not available.
pH (100 ppm in water) 9.76
Vapor Pressure Not available.
o/w Partition Coefficient Not available.
Oxidizing/Reducing Properties Not available.
Additional pH Information Not available.
Viscosity Not available.
NOTE: The physical data presented above are typical values and should not be construed as specifications.
8. Fire and Explosion Information
Fire-fighters should wear positive pressure self-contained breathing apparatus (SCBA) and full turnout gear.
Flammable Limits Not available..
Extinguishing Media Water, fog, carbon dioxide, foam, dry chemical..
Special Firefighting Procedures Fire-fighters whould wear prositive pressure self-contained breathing apparatus (SCBA) and full turnout gear..
9. Reactivity Information
Stability Stable under normal conditions of use and storage.
Imcompatibility Strong acids.
Hazardous Decomposition Products Contact with strongly acidic aqueous systems can release solubilized barium salts, which are highly toxic by ingestion.
10. Handling Precautions
Eye-wash fountains in the work place are recommended. Nuisance dust masks required when the TLV may be exceeded. Rubber gloves, protective eyewear and body protective clothing and shoes are recommended.
11. Satisfactory Materials of Construction
This product is a corrosion inhibitor and is commonly used in contact with all reasonable industrial surfaces. If questions arise concerning the compatibility of this product with any container, please contact B.Labs, Inc., at the phone number on the first page of this MSDS.
Important: Before responding to a spill or leak of this product, review each section of this MSDS. Follow the recommendations given in the Handling Precautions sections. Check the Fire and Explosion Data section to determine if the use of non-sparking tools is merited. Ensure that spilled or leaked product does not come into contact with materials listed as incompatible. If irritating fumes are present, consider evacuation of enclosed areas. Emergency Response Assistance: Emergency technical assistance is available at any time from B.Labs, Inc., by calling (901) 767-2722.

Initially minimize area effected by the spill or leak. Block any potential routes to water systems (e.g., sewers, streams, lakes, etc.). Based on the product’s toxicological and chemical properties, and on the size and location of the spill or leak, assess the impact on contaminated environments (e.g. water systems, ground, air equipment, etc.). There are no methods available to completely eliminate any toxicity this product may have on aquatic environments. Minimize adverse effects on these environments. B.Labs, Inc. can be contacted for technical assistance. Determine if federal, state, and/or local release notification is required (see Regulatory Classifications section of this MSDS). Recover as much of the pure product as possible into appropriate containers. Later, determine if this recovered product can be used for its intended purpose. Address clean-up of contaminated environments. Spill or leak residuals may have to be collected and disposed of. Flushing residual material to an industrial sewer, if present at the site of a spill or leak incident, may be acceptable if authorized approval is obtained. If product and/or spill/leak residuals are flushed to an industrial sewer, ensure that they do not come into contact with incompatible materials. Contact the person(s) responsible for the operation of your facility’s industrial sewer system prior to intentionally flushing spills or leaks of this product to the industrial sewer.

Note: Follow federal, state, and local regulations governing the disposal of waste materials.
Neat Product: Contact your B. Labs representative or B.Labs, Inc., at (901) 278-0330.
Contaminated Materials: Determine if waste containing this product can be handled by available industrial effluent system or other on-site waste management unit. If off-site management is required, contact a company experienced in industrial waste management. This product is not specifically listed in 40 CFR 261 as a Resource Conservation and Recovery Act (RCRA) hazardous waste. However, spill or leak residuals may meet the criteria of a characteristic hazardous waste under this Act. Check the characteristics of the material to be disposed of and/or the physical and reactivity data given in this MSDS for the neat product.

Container Disposal: Empty containers, as defined by appropriate sections of the RCRA, are not RCRA hazardous wastes. However, ensure proper management of any residuals remaining in container.

Not Regulated.
Not Regulated.
Not Regulated.
13. Transportation and Shipping Information
DOT Shipping Information:
IMO/IMDG Shipping Information: IATA Shipping Information:
Unless otherwise stated, the shipping information provided above applies only to non-bulk containers of this product. Proper shipping name and general shipping information may vary depending on packaging and mode of shipment. All products shipped from Buckman locations have been properly packaged and labeled according to appropriate hazardous materials shipping regulations. If any alteration of packaging, product, or mode of transportation is further intended, different shipping information, including but not limited to proper shipping name, RQ designation, and labeling may apply. For further information pertaining to the shipping requirements for this product, contact Buckman’s Transportation Department or DOT Coordinator.
The following Regulations are known to apply to the use and disposal of this product. Additional Federal, State and Local regulations may also be applicable.

SARA (Superfund Admendments and Reauthorization Act)
SARA 302 Extremely Hazardous Substances List…
No components of this product are listed.

Immediate (Acute) Health Hazard

This product contains the following toxic chemical(s) subject to the reporting requirements of section 313 of Title III of the Superfund Amendments and Reauthorization Act of 1986 and 40 CFR part 372 :
Barium metaborate monohydrate
CERCLA (Comprehensive Environmental Response, Compensation and Liability Act)
Barium metaborate monohydrate ….. RQ = 1000 lbs. (453.6 kg)
RCRA (Resource Converation and REcovery Act) Listed Hazardous Waste
No components of this product are listed.
CWA (Clean Water Act) Listed Substances

FDA (Food and Drug Administration)
This product is approved under the following FDA (21 CFR) sections : 176.180: Limitation: For use only as a preservative in coatings and sizings.

TSCA (Toxic Substances Control Act) Applicability
All components are listed on the TSCA Inventory. Registered pesticides are exempt from the requirements of TSCA.

FIFRA (Federal Insecticide, Fungicide, and Rodenticide Act)
This product is a registered pesticide. EPA Reg. No. 1448-17
HMIS/MPCA Rating Health 2 Flammability 0 Reactivity 0

NFPA Ratings Health 2 Flammability 0 Reactivity 0

State Regulations Various State Right To Know Acts …
Non-proprietary hazardous chemicals are listed in Section 2 of this MSDS. Should you require further information on specific proprietary or inert ingredients please contact B. Labs’ Regulatory Affairs Department.
The information on this Material Safety Data Sheet reflects the latest information and data that we have on hazards, properties, and handling of this product under the recommended conditions of use. Any use of this product or method of application which is not described in the Data Sheet is the responsibility of the user. This Material Data Safety Sheet was prepared to comply with the OSHA Hazard Communication regulations. While some components are claimed Trade Secret under OSHA Hazard Communication regulations, all known OSHA hazards associated with the Trade Secret component(s), if contained in this product, are fully disclosed.

B. Labs, Inc. warrants that this product conforms to its chemical description and is reasonably fit for the purpose referred to in the directions for use when used in accordance with the directions under normal conditions. Buyer assumes the risk of any use contrary to such directions.

Seller makes no other warranty or representation of any kind, express or implied, concerning the product, including NO IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS OF THE GOODS FOR ANY OTHER PARTICULAR PURPOSE. No such warranties shall be implied by law and no agent of seller is authorized to alter this warranty in any way except in writing with a specific reference to this warranty.

The exclusive remedy against seller shall be in a claim for damages not to exceed the purchase price of the product, without regard to whether such a claim is based upon breach of warranty or tort.

Any controversy or claim arising out or relating to this contract, or breach thereof, shall be settle by arbitration in accordance with the commercial arbitration rules of the American Arbitration Association, and judgement upon the rendered by the Arbitrator(s) may be entered in any court having jurisdiction thereof.

The opinions expressed herein are those of qualified experts within The Real Milk Paint Co. We believe that the information contained herein is current as of the date of this Safety Data Sheet. Since the use of this information and of these opinions and the conditions of use of this product are not within the control of The Real Milk Paint Co., it is the user’s obligation to determine the conditions of safe use of this product.