Maximum use concentration

Maximum use concentration (MUC) The maximum atmospheric concentration of contaminants in which a respirator cartridge or filter is recommended for use. Can be approximated by multiplying the PEL for the contaminant of concern by the assigned protection factor. 

Maximum Use Concentration (MUC) Also known as the Maximum Use Level or MUL. It is the maximum outside contaminant concenttation a respirator can adequately protect against. The MUC can be calculated from the following relation MUC = PF or FF x PEL (or other standard). The MUC is limited to a chemical cartridge s rated capacity. 

Each subsequent line lists a maximum use concentration (MUC) followed by the classes of respirators that are acceptable for use up to the MUC. Codes for the various categories of respirators, and Assigned Protection Factors (APFs) for these respirators, are listed in Table 3 (page xx). Individual respirator classes are separated by diagonal lines (/). More protective respirators may be worn. The symbol is followed by the classes of respirators that are acceptable for emergency or planned entry into unknown concentrations or entry into IDLH conditions. Escape indicates that the respirators are to be used only... 

Maximum use concentration is taken from commercial literature or it is generally taken that MUC for a gas mask is equal to IDLH, for a full-facepiece respirator is half of IDLH, and for a half-facepiece, air-puiifying respirator is 1 / 5 IDLH. It is important to note that MUC may vary with manufacturer and model. It is important to c[Pg.675]

Maximum use concentration (MUC) means the maximum atmospheric concentration of a hazardous substance from which an employee can be expected to be protected when wearing a respirator, and is determined by the assigned protection factor of the respirator or class of respirators and the exposure limit of the hazardous substance. The MUC can be determined mathematically by multiplying the assigned protection factor specified for a respirator by the required QSHA permissible exposure limit, short-term exposure limit, or ceiling limit. When no QSHA exposure limit is available for a hazardous substance, an employer must determine an MUC on the basis of relevant available information and informed professional judgement. 

B) Maximum Use Concentration (MUC.) (1) The employer must select a respirator for employee use that maintains the employee s exposure to the hazardous substance, when measured outside the respirator, at or below the MUC. 

The toxicity of terpene alcohols when used as fragrance ingredients has been intensively reviewed [77]. At concentrations likely to be encountered by consumers, these chemicals are considered nonirritating to human skin. At the present maximum use concentrations, their potential for eye irritation is considered minimal. 6,7-Dihydroxy geraniol is a potent skin sensitizer and has been prohibited in fragrance materials. Linalool may contain impurities or oxidation products that are strong sensitizers. Famesol is a weak sensitizer so that its use in fragrance materials has been restricted [77]. 

Type of Chemical Cartridge Respirator Maximum Use Concentration (ppm)... 

The purpose of establishing an IDLH exposure concentration is to ensure that the worker can escape without injuty or irreversible health effects from an IDLH concentration in the event of failure of the respiratory protective equipment. The IDLH is considered a maximum concentration above which only highly reliable breathing apparatus providing maximum worker protection is permitted. As IDLH values are set conservatively, any approved respirator may be used up to its maximum use concentration below the IDLH. 

A system of local or general exhaust is recommended to keep employee exposures below the airborne exposure limits. Local exhaust ventilation is generally preferred because it can control the emissions of the contaminant at its source, preventing dispersion of it into the general work area. If the exposure limit is exceeded, a half-face dust/mist respirator may be worn for up to ten times the exposure limit or the maximum use concentration specified by the appropriate regulatory agency or respirator supplier, whichever is lowest. A full-face piece dust/ mist respirator may be worn up to 50 times the exposure limit, or the maximum use... 

Cade oil is widely used in topical preparations for the treatment of parasitic skin diseases and eczema in antiseptic wound dressings, analgesic and antipruritic preparations, and dermatologic creams and ointments also in antidandruff shampoos, among others. Rectified cade oil is used as a fragrance component in soaps, detergents, creams, lotions, and perfumes. Maximum use level reported is 0.2% in perfumes. Maximum use concentration of cade oil in cosmetics ranges from 1 % to 5%. ... 

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