Knowledge Base
 
Cleanroom Classification
 
Glossary of Examination Gloves
  AQL Permeation
  ASTM Primary Skin Irritation Test
  Industrial Gloves/B Grade Gloves Rhinitis
  Elongation Sensitization
  Latex Tensile Strength
  Leaching Vulcanization
   
Glossary of Leather Gloves
  Cape or Capeskin Clute Cut
  Cuff Fourchette
  Gauntlet Grain
  Gunn Cut Gusset
  Split Welt
 
 

Cleanroom Classification:

A cleanroom is an area or enclosure in which the air has to be cleaned to a defined particle limit, usually in "particles per cubic foot". In the United States most cleanrooms are discussed in terms of Classification Limits. For example, a "Class 1000" cleanroom means that a maximum of only 1000 particles 0.5 microns in size would be allowed in a cubic foot of air. A micron is equivalent to one millionth of a meter
.
Small numbers refer to ISO 14644-1 standards, which specify the decimal logarithm of the number of particles 0.1 µm or larger permitted per cubic meter of air. Typical office building air contains from 500,000 to 1,000,000 particles (0.5 microns or larger) per cubic foot of air. A Class 100 cleanroom is designed to never allow more than 100 particles (0.5 microns or larger) per cubic foot of air. Class 1000 and Class 10,000 cleanrooms are designed to limit particles to 1000 and 10,000 respectively.
 
Note that both FS 209E and ISO 14644-1 are based on assumed log-log relationships between particle size and particle concentration. For that reason, there are no "zero" particle concentrations listed. The table locations without entries are N/A ("not applicable") combinations of particle sizes and cleanliness classes. They should not be read as zero.

Because 1 m³ is approximately 35 ft³, the two standards are mostly equivalent when measuring 0.5 µm particles, although the testing standards differ. Ordinary room air is approximately class 1,000,000 or ISO 9.

US FED STD 209E cleanroom standards

Class

maximum particles/ft³

ISO
equivalent

≥0.1 µm

≥0.2 µm

≥0.3 µm

≥0.5 µm

≥5 µm

1

35

7

3

1

 

ISO 3

10

350

75

30

10

 

ISO 4

100

 

750

300

100

 

ISO 5

1,000

 

 

 

1,000

7

ISO 6

10,000

 

 

 

10,000

70

ISO 7

100,000

 

 

 

100,000

700

ISO 8

ISO 14644-1 cleanroom standards

Class

maximum particles/m³

FED STD 209E
equivalent

≥0.1 µm

≥0.2 µm

≥0.3 µm

≥0.5 µm

≥1 µm

≥5 µm

ISO 1

10

2

 

 

 

 

 

ISO 2

100

24

10

4

 

 

 

ISO 3

1,000

237

102

35

8

 

Class 1

ISO 4

10,000

2,370

1,020

352

83

 

Class 10

ISO 5

100,000

23,700

10,200

3,520

832

29

Class 100

ISO 6

1,000,000

237,000

102,000

35,200

8,320

293

Class 1000

ISO 7

 

 

 

352,000

83,200

2,930

Class 10,000

ISO 8

 

 

 

3,520,000

832,000

29,300

Class 100,000

 

 

Glossary of Examination Gloves:

AQL
The U.S. Food and Drug Administration enforce Acceptable Quality Level (AQL) standards for all gloves. This quality specification relates to a glove's freedom from pinholes and typically refers to the barrier protection confidence level. The AQL is used by manufacturers to identify the maximum number of allowable defects (pinholes) per 100 units. A lower AQL number represents a higher quality product. Gloves inspected to an AQL of 2.5 must have fewer than 2.5 defects for every 100 gloves. The FDA specifies an AQL of 1.5 for surgical gloves and 2.5 for exam gloves.

ASTM
The American Society of Testing and Materials (ASTM) and various international groups develop standards and test methods for exam gloves and a variety of other products. Established in 1898, the nonprofit ASTM publishes voluntary consensus principles for materials, products, systems and services in a variety of industries. The FDA uses some of the standards and specifications developed by the ASTM to establish its requirements for examination gloves.

Industrial Gloves/B Grade Gloves
Commonly called industrial grade gloves or off-line gloves, these disposable gloves are designed for non-medical usage. They are ideal for any type of general-purpose use and serve as an excellent entry-level non-medical glove.

Elongation
Elongation relates to material’s elasticity. In other words, how far, in percentage of the original sample length, the glove stretches before it breaks. A glove with a higher elongation will stretch more before breaking.

Latex
Natural latex rubber is manufactured from a variety of plants, but mainly from the rubber tree. Like maple trees, rubber trees are tapped to collect their milky sap-like liquid. Latex exam gloves are made by dipping molds that look like hands into containers of liquid latex and chemicals. Once hardened, the finished product is stripped off the mold, packaged and sterilized.

Leaching
A glove manufacturing cleaning process, in which excess chemicals and/or latex protein are dissolved and washed away from the gloves.

Permeation
The movement of a substance through a thin film, such as an exam glove, on a molecular level. The chemical permeation of exam gloves can be measured in accordance to the Breakthrough Time (BTT), which is how long it takes a chemical to establish a permeation rate of one milligram per square meter, per minute through the protective coating. Gloves with the highest BTT offer the best resistance to chemicals.

Primary Skin Irritation Test
Testing to identify certain material that can trigger skin irritation. The test material, such as a piece of glove material, is attached to the skin of test subjects, such as rabbits or guinea pigs. After a period of time, the sites of application are evaluated for irritation.

Rhinitis
Inflammation of the mucous membrane lining the nose. Rhinitis actually describes a group of symptoms that include runny nose, itching and sneezing. These symptoms may develop as a result of colds or environmental irritants, such as allergens, and can last for weeks or even longer.

Sensitization
The process of developing an allergy. According to a latex allergy alert published by the National Institute of Occupational Safety and Health (NIOSH), the incidence of latex sensitization among healthcare workers is estimated to be between 8 and 12 percent.

Tensile Strength
How much force in pounds per square inch (psi) is required to stretch an exam glove until it breaks. A higher tensile strength implies a stronger glove.

Vulcanization
A type of manufacturing process in which latex exam gloves are treated and hardened from gel form into a solid state inside a heating oven. This curing process is necessary so that the polymer chains of the rubber elastomers are cross-linked, giving latex exam gloves the elasticity. Curing agents can involve a variety of chemicals, including peroxides and agents such as ethylene glycol dimethacrylate, trimethylolpropane and trimethacrylate.

 

Glossary of Leather Gloves:

Cape or Capeskin:
A superior thin leather made from the skin of South African hair sheep.

Clute Cut:
A glove style with a one piece palm with no seam at the base of the finger. There are seams along the fingers
on the inside.

Cuff:
The cuff is the part of the glove extending beyond the palm that covers the wrist and part of the forearm.

Fourchette:
The piece of leather sewn between the fingers on some kinds of gloves. Also known as the sidewall or gusset.

Gauntlet:
A very long cuff to protect the forearm.

Grain:
The side of the leather that had the hair, i.e. the outside. Full Grain has the original surface, whereas corrected
grain has been abraded to make the leather smoother and more uniform.

Gunn Cut:
A glove style with seams at the base of the fingers. The seams between the fingers are on the back of the glove.

Gusset:
The piece of leather sewn between the fingers on some kinds of gloves. Also known as the sidewall or fourchette.

Split:
When a thick piece of leather is split into two thinner pieces, the top piece will have grain (Top Grain) and the
bottom piece will be suede on both sides. The bottom piece is the split.

Welt:
A thin piece of leather sewn into the seam to strengthen it. Often a welt is used in the seam at the crotch of the
thumb and the base of the finger.