Tensile Strength of Disposable Gloves

Tensile Strength: The level of force required to break a material.

Among the characteristics you'll want to consider when evaluating disposable gloves is tensile strength. Tensile strength, or the level of force required to break a glove, is an important indicator of glove quality. Tensile strength is measured in MPa, or megapascals. Using a tensile test machine (see reference image below), glove material is stretched from both ends by the machine until it breaks.

ASTM, the organization that sets the technical and performance standards for disposable gloves, has established the following standards for the tensile strength of nitrile exam gloves (ASTM D412):

• Before aging: 14 MPa
• After aging: 14MPa

The minimum standards for latex gloves are as follows:

• Before aging: 18 MPa
• After aging: 14MPa

ASTM has set a higher 'before aging' minimum standard for latex gloves (versus nitrile gloves) likely because latex is less durable than nitrile.

In case you didn't know: aging is the process of simulating a glove's physical condition at the end of its shelf life by placing it in a heating chamber (per ASTM D573). This is otherwise known as 'accelerated aging'. The 'accelerated aging' for exam gloves is 166 hours at 70°C, or otherwise 24 hours at 100°C. However, when stored properly, mostly gloves will not lose strength to the extent shown in 'after aging' test results.

As a buyer or user of disposable gloves, you may refer to the specification sheet of a glove in order to learn about its tensile strength. 

Above is the specification table for Synguard Exam Grade Nitrile Gloves (SKU: NGPF7002). Synguard is a brand belonging to INTCO Medical, one of the world's leading manufacturers of disposable gloves. As shown above, the tensile strength of Synguard is 14 MPa before and after 'accelerated aging', which meets the ASTM D6319 standards for nitrile examination/medical gloves.

Keep in mind that while exhibiting an MPa at or above minimum standards is important, a glove should not possess too much strength, otherwise it may be difficult to don or use.

RELEVANT ASTM DOCUMENTS FOR REFERENCE:

D6319 - Standard Specification for Nitrile Examination Gloves for Medical Application

D412 - Test Methods for Vulcanized Rubber and Thermoplastic Elastomers - Tension

D573 - Test Method for Rubber - Deterioration in an Air Oven

D3767 - Practice for Rubber - Measurement of Dimensions

D5151 - Test Method for Detection of Holes in Medical Gloves

D5712 - Test Method for Analysis of Aqueous Extractable Protein in Latex, Natural Rubber, and Elastomeric Products Using the Modified Lowry Method

D6124 - Test Method for Residual Powder on Medical Gloves

D6499 - Test Method for Immunological Measurement of Antigenic Protein in Hevea Natural Rubber (HNR) and its Products