Nose clips

Following receipt of more definite information, production of numkK for traitiiftg purpiM es, practically in exact duplication of the Britisli type, was Iiegim in this country in July, 1917. The facepiece of this type wn,s made of rul>lK riz( d cloth and included celluloid eyepieces. It had h rublier mouthpiece and nose clip similar to the British. 

The Yorld War tyj>c of mask with its uncomfortable nose clip and mouthpic M had a doubh line of protection. Projier fit of the facepieiM was hence not vital us it is with the present musk. A.s the integrity of the present ma.sk d< iHmd.s U K>ii pro M r fitting, its imi>ortanco cannot he too strongly emphasized. 

On arriving at the emplacement we met a very thick cloud of the same stuff drifting from the front line system. As it seemed to have no effect on the eyes I gave orders for all to put on their mouthpieces and nose clips so as to breathe none of the stuff, and we carried on. 

For those personnel working in low risk areas, the use of a paper comfort mask should be strongly discouraged. These masks do not provide a good seal around the mouth and nose and do not conform to the standards required for protection from lead-in-air. As a minimum standard, only those paper masks specifically designed for particulates and welding (with neoprene face seals and adjustable nose clips)... 

We have studied hundreds of experimental exposures of volunteers and patients to inhaled NO for short periods (less than 1 hr) (Frostell et al., 1993a Hogman et al., 1993a,c). The subjects wore a nose clip and breathed... 

The Americans suffered 85 casualties with 8 deaths, approximately 33% of their battalion. The problem was a lack of discipline. Because a good American mask was not yet available, the soldiers were issued two gas masks a French M2, which was comfortable but not extremely effective and a British small-box respirator (SBR), which was effective but uncomfortable with its scuba-type mouthpiece and nose clip. At the first sign of gas, some of the men could not find their gas masks in time. Others were able to get their SBRs on, but then either removed their masks too quickly or decided to switch to the more comfortable French mask and were gassed in the process.27... 

Fig. 2-19. A schematic diagram showing the Ml Service Gas Mask. The Ml eliminated the nose clip and mouthpiece of the box respirators of World War I vintage. By directing the incoming air over the eyepieces, it also helped eliminate lens fogging. Photograph Chemical and Biological Defense Command Historical Research and Response Team, Aberdeen Proving Ground, Md.

Stearic acid was successfully delivered to the human oral cavity by emulsions at 67-69 °C where this stimulus is in liquid form [4, 22]. Detection thresholds were identified by orthonasal olfaction, retronasal olfaction, gustation, and a multimodal presentation where the lipid emulsion was placed in the oral cavity in the absence of nose clips [4]. Although measured at different temperatures, intensity responses for stearic acid were similar to the 18-carbon cis- unsaturated fatty acids linoleic and oleic acid. Oral detection thresholds for stearic acid in the human oral cavity with emulsions, yielded thresholds near 0.032% (w/v) [4, 22]. In addition, most study participants were able to detect stearic acid in the oral cavity [4,22]. 

In all cases, fitting, cleaning, maintenance, training and proper storage are necessary. The simpler face-pieces are not for shared use. In certain circumstances, a bearded worker can use a mouthpiece respirator with a nose-clip. For information on selection and use of respiratory equipment refer to manufacturers information and to standards or codes of practice (in the USA, MSHA and OHSA). 

A re-breather is a rubber bag, a bit like a hot water bottle, with a hose and a mouthpiece, and a nose-clip attached. The bag fies on your chest over the lifejacket. 

Odorants were presented twice each in random order via the retronasal route in OPC to 18 subjects, after retronasal identification learning. A nose clip was used to prevent any smelling of the odorant in the OPC until the OPC was in the oral cavity, and the lips closed. Correct identification percentages are in cells with gray backgrounds. Overall retronasal identifications were correct on 86% of trials (median). 

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