Chapter I General Provisions
Article 1.0.1 In order to ensure that the city road lighting can create as vehicle drivers and pedestrians to see good visual environment, to guarantee traffic safety, improve transportation efficiency, facilitate people's lives, prevent criminal activity and the effect of beautifying the urban environment, specially formulated This standard.
Article 1.0.2 This standard applies to the road design of new, expanded and rebuilt roads and special places associated with roads. It is not applicable to the design of tunnel lighting.
Article 1.0.3 The design principle of road lighting is safe and reliable, advanced technology, economical and reasonable, energy saving and convenient maintenance.
Article 1.0.4 In addition to the implementation of this standard, road lighting design shall comply with the relevant national or industry standards or norms.
Chapter II Lighting Standards
Article 2.0.1 Urban road lighting standards are divided into five levels according to express roads, trunk roads, secondary trunk roads, branch roads and residential roads.
Article 2.0.2 The illumination of the expressway, trunk road, secondary trunk road and branch road shall meet the four indicators of average brightness (or illumination), brightness (or illumination) uniformity, glare limitation and inductiveness. The roads in residential areas mainly for non-motor vehicles and pedestrians should meet the single evaluation indicators of average illumination.
Clause 2.0.3 The road lighting standards at all levels are shown in Table 2.0.3.
For details, please click to download: Cjj45-91-city road lighting design standard.rar
Aviation headphones are used in airplanes, cars, subways, etc., to facilitate passengers to listen to audio and watch videos to enjoy a pleasant journey.
The aviation earphones are mostly disposable, so the structure is extremely simple, the shape is relatively ordinary, the materials are small, and the annual usage is very large. The number of inquiry can reach several million or even tens of millions, so the cost is very cheap. earphones can cost as little as 10-15 cents. Therefore, they are disposed of as garbage after used, and passengers could take it away for personal use.
Styles can be divided into on ear headphones and in ear earphones.
Functional difference: power, impedance, and sensitivity etc. are also different. Airplane Headphone is mainly customized according to the equipment, place and user used. For example, 1 customer might require 300 ohms impedances , and other customers may need 32 ohms. For adults, the sensitivity may reach 100DB or more.To children, the sensitivity may be around 85-90 DB.
In addition, aviation headphones are not all disposable ones. Some first-class cabins need to be equipped with headphones with good noise reduction, sound quality and functions. So the price will be much more expensive.
Airline Headphones,Airline Earphones,Airplane Headphones,Airline Noise Cancelling Headphones
Shenzhen Linx Technology Co., Ltd. , https://www.linxheadphone.com