Cain W S, Turk A
Am Ind Hyg Assoc J. 1985 Mar;46(3):115-26. doi: 10.1080/15298668591394527.
LP-gas derives warning properties from the odorants ethyl mercaptan or thiophane. Laboratory tests have implied that the average person has the ability to smell the odors before leaking LP-gas reaches one-fifth its lower limit of flammability. Generally, however, laboratory tests ignore or discard persons with a poor sense of smell, especially the elderly and persons with certain types of hyposmia. Some persons who apparently can smell the warning agents when directed may otherwise fail to notice or identify them. Elderly men seem particularly vulnerable to instances of incidental anosmia and olfactory agnosia. Psychophysical testing of the warning agents has been rather unsophisticated. There exists neither a standard protocol for testing nor adequate specification of the perceptual properties that might make one warning agent better than another. Without such developments, improvement in warning agents will fail to occur. Possible improvements include increases in concentration, the use of blends to insure more uniform delivery of agent and, to decrease the perceptual vulnerability of relatively insensitive people, use of agents with favorable psychophysical (stimulus-response) functions and use of agents with favorable adaptation characteristics. Even without a change in existing products, it seems advisable to learn more about the vulnerability of LP-gas users and to employ educational means to reduce risks.
液化石油气的警示特性源自乙硫醇或噻吩等气味剂。实验室测试表明，在泄漏的液化石油气达到其可燃下限的五分之一之前，普通人有能力闻到这些气味。然而，一般来说，实验室测试会忽略或排除嗅觉不佳的人，尤其是老年人和患有某些类型嗅觉减退的人。一些人在被引导时显然能闻到警示剂的气味，但在其他情况下可能无法注意到或识别它们。老年男性似乎特别容易出现偶发性嗅觉丧失和嗅觉失认症。对警示剂的心理物理学测试相当简单。既没有测试的标准方案，也没有对可能使一种警示剂优于另一种警示剂的感知特性进行充分的说明。没有这些进展，警示剂就无法得到改进。可能的改进包括提高浓度、使用混合物以确保更均匀地释放警示剂，以及为降低相对不敏感人群的感知易感性，使用具有良好心理物理学（刺激 - 反应）功能的警示剂和具有良好适应特性的警示剂。即使现有产品不变，了解更多液化石油气使用者的易感性并采用教育手段降低风险似乎也是可取的。
