- O -

The following are commonly used abbreviations, acronyms, and a glossary of specialized terms starting with the letter: 

— O —

Oakland Memorial Hospital – medical facility; Oakland, NE – (acronym, OMH).

o-anisidine – chemical compound – CAS number 90-04-0. ACGIH TLV = 0.1 PPM (0.5 mg/m³),  IDLH = 50  ppm, NIOSH REL 0.5 mg/m³, potential occupational carcinogen;  TWA, OSHA PEL 0.5 mg/m³.

obsidian — rock classification, texture —

obvious — that which is plain or evident; a condition or fact that could not be ignored or overlooked by a reasonable observer while visually or physically observing the property.   Source (ASTM, 2004).

occupants — those tenants, subtenants, or other persons or entities using the property or a portion of the property.   Source (ASTM, 2004).

o-chlorobenzylidene malononitrite – chemical compound – CAS number 2698411. ACGIH TLV = 0.05 ppm (0.39 mg/m³) ceiling; NIOSH REL 0.05 ppm (0.4 mg/m³) ceiling; NIOSH IDLH 2 mg/m³, OSHA PEL 0.05 ppm (0.4 mg/m³) ceiling; LEL unknown.

octane – chemical compound – see NIOSH.

o-dichlorobenzene – chemical compound – see NIOSH.

o-dichlorobenzene (acronym: o-DCB; synonyms: ortho-dichlorobenzol, diatin, dowtherm e, chloroben, bilatin db)  – organic chemical – (MCL = 0.6 mg/L).

Ogallala Community Hospital – medical facility; Ogallala, NE – (acronym, OCH).

ogliocene – geologic time, epoch – (symbol: To, color yellow and ocher) approximately 33.7 – 23.8 MYA; approximate duration: 11-12 MY.

oil & grease

oil mist (mineral) – chemical compound – see NIOSH.

Oklahoma (abbreviation: OK).

Old Red sandstone – geologic stratigraphic description.

Oldman formation – geologic stratigraphic description.

olivenite — Cu₂(OH)(AsO₄) — (phosphate mineral).

olivine theoleiite — rock classification, igneous — volcanic basalt. 

oölitic (abbreviation: oö).

operation & maintenance (acronym: O&M).

ordovician – geologic time, period – (symbol: O, color: red) approximately 490-443 MYA; approximate duration: 60-70 MY).

Organic clays of medium to high plasticity – USCS soil classification – (symbol: OH).

orpiment — As₂S₃ — (sulfide mineral).

orthoclase (abbreviation: orth).

orthoclase —K(AlSi₃O₈) — (silicate mineral).

osmium — chemical element — (abbreviation: Os).

osmium tetraoxide (as Os) – chemical compound – see NIOSH.

Osmong General Hospital – medical facility; Osmond, NE – (acronym, OGH).

other historical sources—any source or sources other than those designated in 7.3.4.1 through 7.3.4.8 that are credible to a reasonable person and that identify past uses of the property. The term includes, but is not limited to: miscellaneous maps, newspaper archives, and records in the files and/or personal knowledge of the property owner and/or occupants.   Source (ASTM, 2004).

o-toluidine – chemical compound – see NIOSH.

ounce — unit of measure, weight —   (abbrv: oz. — ) = 16 dr = 28.35 g

outcrop (abbreviation: otcp).

owner — generally the fee owner of record of the property.   Source (ASTM, 2004).

oxalic acid – chemical compound – see NIOSH.

oxamyl – chemical compound – (synonyms: vydate, thioxamyl, dioxamyl, DPX 1410, dupont 1410) – organic chemical – (MCL = 0.02 mg/L).

Oxford clay – geologic stratigraphic description.

oxygen (abbreviation: O). — chemical element.

oxygen difluride – chemical compound – see NIOSH.

oxygen scavengers

ozone – chemical compound – see NIOSH.