Documentary standards define agreed-upon terminology or standard language for a field of science, engineering, or technology; they are agreed-upon means for conducting measurements; agreed-upon performance characteristics of instruments or commercial products; and particularly, they are documented agreements on means to facilitate trade and commerce.


1. Standards for Nanotechnology

Illustrative examples of documentary standards available for nanomaterials are listed in the table below. For a comprehensive list of nanotechnology-related standards, please visit each organization’s website.

2. Safety assessment of nanomaterials

Around the world, there are numerous standards-setting groups that are involved in developing nanotechnology standards. The JRC is at the heart of EU efforts to understand and assess nanomaterials and participates in various collaborative research projects with European and international partners. Furthermore, its work on methods for assessing the safety of nanomaterials is closely connected to the OECD’s Test Guidelines Programme and its Working Party on Manufactured Nanomaterials. The JRC also collaborates with the European Committee for Standardisation (CEN) and the International Organisation for Standardisation (ISO) regarding their activities on the characterisation of nanomaterials. Some of the leading standards-setting organizations and their relevant nanotechnology committees are (in no particular order):

  • International Standardization Organization (ISO) Technical Committee (TC) 229 on Nanotechnologies.
  • ASTM International’s Committee E56 (Nanotechnology) (formerly known as the American Society for Testing and Materials).
  • International Electrotechnical Commission Technical Committee 113 (Nanotechnology Standardization for Electrical and Electronics Products and Systems).
  • Institute of Electrical and Electronics Engineers’ Nanotechnology Council.
  • European Committee for Standardisation (CEN).
  • International Organisation for Standardisation (ISO).


The basis of the standard has to do with identifying the particular hazard and putting together the correct combination of PPE based on the probable impact and exposure to that substance. The document categorizes hazards and PPE levels on the following criteria:

  • Level A   To be selected where the hazards are unknown or unquantifiable or when the greatest level of skin, respiratory and eye protection is required.
  • Level B   The highest level of respiratory protection is necessary but a lesser level of skin protection is needed.
  • Level C   The concentration(s) and type(s) of airborne substances is known and the criteria for using air‐purifying respirators are met.


Currently, no single personal protective ensemble can protect the wearer from exposure to all hazards. It is important that the appropriate combination of a respirator, protective ensemble and other equipment be selected based on a conclusive hazard assessment at the scene.


3. Respiratory Mask Protection

Particulate filter efficiency is based on the ability to remove particles greater than 0.3 microns in diameter (median aerodynamic diameter of 0.3 um). The National Institute for Occupational Safety and Health (NIOSH) and European Norms (ENs) employ different test protocols for evaluation of air-purifying particulate respirators commonly referred to as filtering facepiece respirators (FFR). The relative performance of the NIOSH-approved and EN-certified ‘Conformité Européen’ (CE)-marked FFR is not well studied. NIOSH requires a minimum of 95 and 99.97% efficiencies for N95 and P100 FFR, respectively; meanwhile, the EN requires 94 and 99% efficiencies for FFRs, class P2 (FFP2) and class P3 (FFP3), respectively.


  • EN149: 2001 European Standard

A filtering half mask is one in which the facepiece consists entirely or substantially of filter material or comprises a facepiece in which the main filter(s) from an inseparable part of the device. Respirators which meet the requirements of EN149: 2001 are designed to protect against solids, water-based aerosols and oil-based aerosols. There are three classes of protection detailed in EN149: 2001 – FFP1, FFP2 & FFP3 (FFP stands for Filtering Face Piece) are classified according to filter efficiency.

  • FFP1 (80% Filter efficiency) Suitable for protection from non‐toxic contaminants in concentrations up to 4 x OEL or 4 x APF.
  • FFP2 (94% Filter efficiency) Suitable for protection from low to average toxicity contaminants in concentrations up to 12 x OEL or 10 x APF.
  • FFP3 (99% Filter efficiency) Suitable for protection from toxicity contaminants in concentrations up to 50 x OEL or 20 x APF.

OEL = Occupational Exposure Limit          APF = Assigned Protection Factor

A simple colour-coding system exists to help you easily distinguish each product’s filtering performance.


Class    Separation ability (at 95 L/min airflow)     Allow leakage between mask and face

FFP1      Filter separates 80% of airborne particles             < 22%

FFP2      Filter separates 94% of airborne particles             < 8%

FFP3      Filter separates 99% of airborne particles             < 2%

Disposable Mask Protection Levels

FFP1      Particles larger than 5 microns:   Dust, Fumes, Aqueous mists, Oils based mists

FFP2      Particles between 2&5 microns:  Fine dust, Fibers, Aqueous mists, Oils based mists

FFP3      Particles less than 2 microns:       Very fine dust, Fibers, Aqueous mists, Oils based mists


  • NIOSH of the US government

The NIOSH (National Institute for Occupational Safety and Health) respiratory protection approval regulation (42 CFR 84) defines the term “N95” to refer to a filter class, not a respirator.

  • Classes of filters: Filters are classified by efficiency and performance characteristics against non‐oil and oil‐containing hazards. There are nine classes of filters. Three levels of filter efficiency, each with three categories of resistance to filter efficiency degradation.
  • Filter efficiency: Levels of filter efficiency are 95%, 99%, and 99.97% Under NIOSH criteria, filter materials are tested at a flow rate of 85 lpm for penetration by particles with a median aerodynamic diameter of 0.3 um and if certified are placed in one of the following categories: Type 100 (99.7% efficient), Type 99 (99% efficient), Type 95 (95% efficient).
  • Categories of filters: Categories of resistance to filter efficiency degradation are labelled: N (Not resistant to oil) R (Resistant to oil) P (Oil proof).
  • NIOSH‐Approved Particulate Filtering Facepiece Respirator: There are seven classes of filters for NIOSH‐approved filtering facepiece respirators available at this time. Ninety‐five percent is the minimal level of filtration that will be approved by NIOSH. The N, R and P designations refer to the filter’s oil resistance as described below.

A simple colour-coding system exists to help you easily distinguish each product’s filtering performance.


N95, N99, N100  ‐ Filters at least 95%, 99%, 99.97% of airborne particles. Not resistant to oil.

R95, R99, R100  ‐ Filters at least 95%, 99%, 99.97% of airborne particles. Somewhat resistant to oil.  

P95, P99, P100   ‐ Filters at least 95%, 99%, 99.97% of airborne particles. Strongly resistant to oil.


Surgical masks are not designed for use as particulate respirators and do not provide as much respiratory protection as an N95 respirator. Surgical masks provide barrier protection against droplets including large respiratory particles. Most surgical masks do not effectively filter small particles from the air and do not prevent leakage around the edge of the mask when the user inhales. N95 Respirators and Surgical Masks, posted 10/15/2009, provides an explanation of the science behind and the similarities/differences between NIOSH-approved particulate respirators and surgical masks.

Surgical mask versus N95 respirator mask


4. Filtering Facepiece Respirator (FFR) Labels

Individual filtering facepiece respirators are required to have the following markings:

  1. Name of approval holder/manufacturer business name, a registered trademark, or an easily understood abbreviation of the applicant/approval holder’s business name as recognized by NIOSH. When applicable, the name of the entity to which the FFR has been private labelled by the approval holder may replace the approval holder business name, registered trademark, or abbreviation of the approval holder business name as recognized by NIOSH.
  2. NIOSH in block letters or the NIOSH logo.
  3. NIOSH Testing and Certification approval number, e.g., TC-84A-XXXX.
  4. NIOSH filter series and filter efficiency level, e.g., N95, N99, N100, R95, P95, P99, P100.
  5. Model number or part number: The approval holder’s respirator model number or part number, represented by a series of numbers or alphanumeric markings, e.g., 8577 or 8577A.

NIOSH recommends the lot number and/or date of manufacture also be included, however, this is not required. Filtering facepiece respirators that are private labelled are required to have the following statement on the packaging as a special S caution and limitation statement identified on the full label and located in the respirator user instructions:

Marketed by xxxxxx (the private label company name).

Produced by xxxxxx (the approval holder company name).

This private label related statement does not need to appear on the exterior surface of the respirator as part of the required name marking.