Shanghai Sunland Industrial Co., Ltd is the top manufacturer of Personal Protect Equipment in China, with 20 years’experience. We are the Chinese government appointed manufacturer for government power,personal protection equipment , medical instruments,construction industry, etc. All the products get the CE, ANSI and related Industry Certificates. All our safety helmets use the top-quality raw material without any recycling material.
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We provide exclusive customization of the products logo, using advanced printing technology and technology, not suitable for fading, solid and firm, scratch-proof and anti-smashing, and suitable for various scenes such as construction, mining, warehouse, inspection, etc. Our goal is to satisfy your needs. Demand, do your best.
Professional team work and production line which can make nice quality in short time.
The professional team provides 24 * 7 after-sales service for you, which can help you solve any problems
The concept can be linked back to the ,first gas mask, (created in ,1847,) whereby air is filtered before being recirculated and the ,first, activated charcoal ,gas mask, created in 1915. Ductless cupboards were ,first, created around 1968.
The ,first, well-documented use of ,gas masks, came in the 9th Century, when ,gas masks, were used in Persia to protect people working in polluted wells. ... But in ,1847,, the world saw one of the most important additions in ,gas,-,mask, technology: charcoal. Charcoal, ...
The ,First Gas Mask,: It has to valves so you can inhale and exhale without inhaling any unhealth substances. It's has bag like screens placed over head or cloth or sponge covering the nose and mouth.Below are pictures of two ,mask, from different time periods. Facts about the inventor:1.) His invention was the ,first, United State patent in ,1847,.2.)
The ,first gas masks, mostly used circular lenses made either of glass, mica or cellulose acetate. With the exception of the latter, these materials were quite brittle and needed frequent replacement. Later on, the Triplex lense style (two layers of glass and one layer of cellulose acetate in between)  became more popular, and alongside the simpler cellulose acetate they became the standard ...
The forerunner to the modern ,gas mask, was invented in ,1847, by Lewis Haslett, a device that contained elements that allowed breathing through a nose and mouthpiece, inhalation of air through a bulb-shaped filter, and a vent to exhale air back into the atmosphere.
The ,gas mask, was invented so people could breathe through a nose or mouth piece fitted with two one way clapper valves: one to permit the inhalation of air through a bulb shape filter, and the other piece is to vent exhaled air directly into the atmosphere. Similar valves that was made for this ,first, device became usable in later ,masks,.
· Robert William Thomson patents the ,first, vulcanised rubber pneumatic tire. 1846 · Dr. William Morton, a Massachusetts dentist, is the ,first, to use anesthesia for tooth extraction. ,1847, · Hungarian, Ignaz Semmelweis invents antisceptics. 1848