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Labels – Surfaces and Conditions

Common application surfaces on which Marking and Labeling Systems are recognized.

Fire extinguisher with UL Mark


Application surfaces

This list includes some of the more common application surfaces on which Marking and Labeling Systems are recognized. All surfaces referenced in Recognitions are considered smooth, flat and rigid unless otherwise specified. Painted surfaces are on metal substrates.

Application surface (abbreviation)

Acrylic  (AC)
Acrylic paint  (AC PT)
Acrylonitrile butadiene styrene  (ABS)
Alkyd paint  (AK PT)
Aluminum  (AL)
Chromate treated metal  (CTM)
Epoxy  (EP)
Epoxy paint  (EP PT)
Epoxy powder paint  (EP PDR PT)
Galvanized steel  (GS)
Melamine  (ME)
Nylon, polyamide  (PA)
Phenolic, Phenol Formaldehyde  (PH)
Polybutylene terephthalate  (PBT)
Polycarbonate  (PC)
Polyester paint  (PER PT)
Polyester powder paint  (PER PDR PT)
Polyethylene  (PE)
Polyethylene terephthalate  (PET)
Polyphenylene oxide/ether  (PPOX)
Polyphenylene sulfide  (PPS)
Polypropylene  (PP)
Polystyrene  (PS)
Polyurethane powder paint  (PUR PDR PT)
Polyvinyl chloride  (PVC)
Porcelain  (PRCLN)
Stainless steel  (SS)
Unsaturated polyester, thermoset  (UP)

Labels for use in special environments

In addition to being evaluated for indoor use, indoor dry use or outdoor use, labels may be evaluated for environmental conditions specific to certain end-product applications. Below is a list of some of the additional conditions for which labels could be evaluated.

Code and additional conditions
C Occasional exposure to Cooking Oil
DD Occasional exposure to Dishwashing Detergents
DL Occasional exposure to Laundry Detergents
E25 Occasional exposure to splashing of gasoline/ethanol blends up to 25% ethanol
E85  Occasional exposure to splashing of gasoline/ethanol blends up to 85% ethanol
F1 Occasional exposure to Fuel Oil No. 1
F2  Occasional exposure to Fuel Oil No. 2
FE  Suitable for use on Fire Extinguisher shells
G Occasional exposure to Gasoline splashing
HZ Suitable for use on Class I, Division 1, Groups C and D Hazardous Location products
Occasional exposure to Kerosene
O Occasional exposure to Lubricating Oil
PL  Also suitable for use on portable ladders
RT(1)  Also complies with UL 514A, UL 60950-1, UL 60335-1, UL 60745-1, UL 60974-1, UL 61058-1 and UL 60065 marking durability rub test requirements


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Compliance Guidelines for Marking and Labeling Systems

Download our guideline

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