This standard specifies the test method for safety helmet.
This standard is applicable to safety helmets specified in GB 2811 and their technical requirements.
2 Normative References
The following standards contain provisions which, through reference in this text, constitute provisions of this standard. For dated reference, subsequent amendments to (excluding correction to), or revisions of, any of these publications do not apply. However, all parties coming to an agreement according to this standard are encouraged to study whether the latest edition of these documents is applicable. For undated references, the latest edition of the normative document is applicable to this standard.
GB/T 1410 "Methods of Test for Volume Resistivity and Surface Resistivity of Solid Insulating Materials"
GB/T 2408 "Plastics-Determination of the Burning Behaviour of Horizontal and Vertical Specimens in Contact with a Small-flame Ignition Source"
GB 2811 "Safety Helmet"
GB/T 14522 "Accelerated Weathering Test Method for Plastics, Coatings and Rubber Materials Used for Machinery Industrial Products"
3 Test Samples
The test samples shall conform to the description of product identification, with complete accessories and effective function.
3.1 Quantity
The total quantity of the test samples shall be determined according to the specific requirements of the test, and the minimum quantity shall meet the requirements of GB 2811.
If the dimension inspection may cause irrecoverable damage to the safety helmet, sample quantity shall be provided individually according to the requirements of GB 2811 to be used for destructive dimension inspection.
3.2 Pretreatment
The tested samples shall be placed in the test room for above 3h, and then pretreated respectively according to the requirements of this section, unless specially stated.
3.2.1 Equipment
3.2.1.1 Temperature regulating chamber
The temperature in the temperature regulating chamber shall be controllable within the range of 50℃±2℃, -10℃±2℃ or -20℃±2℃; the temperature in the chamber shall be uniform; the temperature regulation may be accurate to 1℃; the safety helmet shall be free from touching the inner wall of the chamber.
3.2.1.2 Ultraviolet irradiation chamber
The ultraviolet irradiation chamber inside shall be provided with adequate space to guarantee the safety helmet is placed in a uniform irradiation zone and free from touching the inner wall of the chamber. Ultraviolet irradiation (method A) and xenon lamp irradiation (method B) may be adopted.
Ultraviolet irradiation: the distance from the helmet top to the peak point shall be 150mm±5mm; during normal operation, the temperature in the chamber shall not exceed 60℃; the recommended model of short-pulse high-voltage xenon lamp with 450W bulb shall be XBO-450 W/4 or CSX-450 W/4.
Xenon lamp irradiation: the radiant energy that the wavelength of the xenon lamp is within the range of 280nm~800nm shall be measurable; the blackboard temperature shall be 70℃±3℃; the relative humidity shall be 50%±5%; water shall be sprayed for 18min every other 102min.
3.2.1.3 Water channel
Enough volume shall be provided to make the safety helmet completely immersed in the water. The water temperature shall be controllable within the range of 20℃±2℃.
