GB/T 15972.54-2021Specifications for optical fibre test methods - Part 54: Measurement methods and test procedures for environmental characteristics - Gamma irradiation (English PDF)

Foreword

GB/T 15972 "Specifications for Optical Fiber Test Methods" consists of several parts, and its expected structure and corresponding international standards are.

---Part 10~Part 19.General principles of measurement methods and test procedures (corresponding to IEC 60793-1-10 to IEC 60793-

1-19);

---Part 20~Part 29.Measurement methods and test procedures of dimensional parameters (corresponding to IEC 60793-1-20 to IEC 60793-

1-29);

---Part 30~Part 39.Measurement methods and test procedures of mechanical properties (corresponding to IEC 60793-1-30 to IEC 60793-

1-39);

---Part 40~Part 49.Measurement methods and test procedures of transmission characteristics (corresponding to IEC 60793-1-40 to IEC 60793-

1-49);

---Part 50~Part 59.Environmental performance measurement methods and test procedures (corresponding to IEC 60793-1-50 to IEC 60793-

1-59).

Among them, GB/T 15972.50~59 currently consists of the following parts.

---Part 50.Measurement methods and test procedures for environmental performance constant damp heat;

---Part 51.Environmental performance measurement methods and test procedures dry heat;

---Part 52.Environmental performance measurement methods and test procedures temperature cycling;

---Part 53.Measurement methods and test procedures for environmental performance immersion in water;

---Part 54.Measurement methods and test procedures for environmental performance Gamma irradiation;

--- Part 55.Environmental performance measurement methods and test procedures Hydrogen aging.

This part is part 54 of GB/T 15972.

This section was drafted in accordance with the rules given in GB/T 1.1-2009.

This part replaces GB/T 15972.54-2008 "Specification for optical fiber test methods-Part 54.Environmental performance measurement methods and tests

Procedural Gamma Irradiation.

Compared with GB/T 15972.54-2008, the main technical changes in this part are as follows.

---The normative references of GB/T 15972.46 have been added (see Chapter 2);

---Added Chapter 3 background overview (see Chapter 3);

--- Deleted Appendix A and put the content in the newly added Chapter 3 (see Appendix A of the.2008 edition);

---Added the danger warning in the overview part of the experimental device (see 4.1);

---Deleted the specific requirements of the light source, optical filter/monochromator (see 3.2, 3.3 of the.2008 edition);

--- Amend "A2.1 and A2.2 multimode fiber (refractive index quasi-abrupt and abrupt)" to "A2 multimode fiber (refractive index quasi-abrupt)"

Mutations and mutants)" (see 4.8.2, 3.7.3 of the.2008 edition);

---Modified the optical power requirements of the light source coupled into the sample, and changed "not greater than 1.0µW" to "equal to 1.0µW" (see 4.10,.2008

1 Scope

This part of GB/T 15972 specifies the measurement methods and test procedures for evaluating the performance of optical fibers and cables in a given gamma radiation environment.

This part is applicable to the determination of cabled or uncabled type A1, A2 type multimode fiber and type B single-mode fiber due to exposure to gamma radiation.

The raw radiation induction attenuation value. This section does not apply to the measurement of non-light-transmitting component materials in optical cables. If the optical cable material is exposed to radiation, it will

If deterioration occurs, further research and other measurement methods are needed.

Note. The applicability of this test to other types of optical fibers is under study. Refer to IEC /T R62283 for detailed background information.

2 Normative references

The following documents are indispensable for the application of this document. For dated reference documents, only the dated version applies to this article

Pieces. For undated reference documents, the latest version (including all amendments) is applicable to this document.

GB/T 15972.40-2008 Optical fiber test method specification Part 40.Transmission characteristic measurement method and test procedure Attenuation

(IEC 60793-1-40.2001, MOD)

GB/T 15972.44 Specification for optical fiber test methods Part 44.Measurement methods and test procedures for transmission characteristics Cut-off wavelength

(GB/T 15972.44-2017, IEC 60793-1-44.2011, MOD)

GB/T 15972.46 Optical fiber test method specification Part 46.Transmission characteristic measurement method and test procedure Transmittance change

(GB/T 15972.46-2017, IEC 60793-1-46.2001, MOD)

3 Background overview

When exposed to gamma radiation, the attenuation of cabled or uncabled fiber will usually increase. This is mainly due to the defects in the glass

It is caused by trapping electrons and holes decomposed by radiation (that is, forming a "color center"). This test procedure includes two main states. suitable for evaluation

Estimate the low-dose state of the environmental background radiation effects and the high-dose state suitable for evaluating the harmful nuclear environmental effects. Adopt similar to

Method A (cut-off method) in GB/T 15972.40-2008 can be used to test the effects of environmental background radiation. By monitoring the test specimens exposed to

The power before, after and during gamma irradiation can be used to test harmful nuclear environmental effects. Reduction of color centers caused by light (photobleaching) or heat

The recovery effect (reduce the attenuation of radiation induction). The recovery effect can occur in a wide time range, which depends on the irradiation time and annealing temperature.

degree. This complicates the characteristics of attenuation changes caused by irradiation, because attenuation is related to many variables, including test environment temperature, sample

The structure, the total dose and dose rate applied to the specimen, and the level of light used to measure it.

4 Test device