Case Title: Johnson v. American Standard

Citation: 43 Cal. 4th 56 original opinion

Docket Number: S139184

State: california

Court: California Supreme Court

Date: 2008-04-03T00:00:00Z

Document:
1
Filed 4/3/08 
 
 
 
IN THE SUPREME COURT OF CALIFORNIA 
 
 
 
WILLIAM KEITH JOHNSON, 
) 
 
 
) 
 
Plaintiff and Appellant, 
) 
 
 
) 
S139184 
 
v. 
) 
 
 
) 
Ct.App. 2/5 B179206 
AMERICAN STANDARD, INC., 
) 
 
) 
Los Angeles County 
 
Defendant and Respondent. 
) 
Super. Ct. No. BC 287442 
___________________________________ ) 
 
This product liability action raises a question of first impression in 
California; i.e., whether we should adopt the “sophisticated user” doctrine and 
defense to negate a manufacturer’s duty to warn of a product’s potential danger 
when the plaintiff has (or should have) advance knowledge of the product’s 
inherent hazards.  The defense is specifically applied to plaintiffs who knew or 
should have known of the product’s hazards, and it acts as an exception to 
manufacturers’ general duty to warn consumers.  (See Rest.2d Torts, § 402A.) 
The federal courts have adopted the doctrine as an affirmative defense in 
diversity cases, and they predict that we will do the same.  (In re Air Crash 
Disaster (6th Cir. 1996) 86 F.3d 498, 522; In re Related Asbestos Cases (N.D.Cal. 
1982) 543 F.Supp. 1142, 1151 (In re Asbestos).)  For the reasons discussed below, 
we conclude that the sophisticated user defense applies in California.  We affirm 
the Court of Appeal judgment and remand for further proceedings consistent with 
this holding. 
 
2
FACTS AND PROCEDURAL HISTORY 
Plaintiff William Keith Johnson is a trained and certified heating, 
ventilation, and air conditioning (HVAC) technician.  He began working in the 
HVAC field in 1996 when he first received training at ITT Technical Institute, 
where he completed a year-long course on HVAC systems.  Plaintiff continued to 
work as an HVAC technician until 2002.  He received additional training and 
certifications, both on and off the job, including an Environmental Protection 
Agency (EPA) “universal” certification after he passed a five-part exam.  
“Universal” certification is the highest certification an HVAC technician can obtain 
from the EPA, and it allows those certified to work on, and purchase, refrigerant 
for large commercial air conditioning systems.  (40 C.F.R. §§ 82.154 (m), 82.161 
(2007).)  “Universally” certified technicians are trained professionals, and their 
tasks include brazing (welding) and part replacement. 
 
Large air conditioning systems commonly use R-22, a 
hydrochlorofluorocarbon refrigerant.  The refrigerant can decompose into 
phosgene gas when exposed to flame or high heat, as could happen while a 
technician is brazing air conditioner pipes containing residual refrigerant.  
Exposure to phosgene gas may cause numerous health problems, and 
manufacturers and HVAC technicians have generally known of the dangers this 
exposure could cause since as early as 1931.  The dangers and risks associated with 
R-22 are noted on Material Safety Data Sheets (MSDS’s).  (Cal. Code Regs., tit. 8, 
§ 5194, subd. (g)(1), (2).)1  The purpose of MSDS’s is to inform those who may 
                                              
1 
In July of 2004, California Code of Regulations title 8, section 5194, 
subdivision (g), was amended in several places.  The changes, however added little 
substance to what was required of employers, and so the current requirements 
accurately indicate the obligations plaintiff’s employers had and the information 
that plaintiff should have known about the product when he was exposed to it. 
 
3
come into contact with potentially hazardous chemicals about their dangers.  (See 
Cal.Code Regs., tit. 8, § 5194, subd. (g).)  Employers are required to use the MSDS 
to train and educate their employees about the chemicals and dangers to which they 
may be exposed on the job.  (See Cal. Code Regs., tit. 8, § 5194, subd. (h).)2  
Among other things, employers are required to tell employees where they can find 
the MSDS’s, how to read them, how to detect the presence of dangerous materials, 
and how to protect against possible health hazards from those materials.  (Cal. 
Code Regs., tit. 8, § 5194, subd. (h)(2)(C), (D), (E), (F).)  Beginning in 1997, every 
time he purchased the refrigerant R-22, plaintiff received, and sometimes read, an 
MSDS. 
In June 2003, plaintiff filed his first amended complaint, suing various 
chemical manufacturers, chemical suppliers, and manufacturers of air conditioning 
equipment, including defendant American Standard, Inc.3  One of the systems on 
which plaintiff worked in 2002 was located at the Bank of America Del Amo 
branch.  Plaintiff specifically alleged that he brazed refrigerant lines on an 
evaporator defendant manufactured in 1965 that contained R-22 refrigerant, 
creating and exposing him to phosgene gas.  Plaintiff alleged that the maintenance 
and repairs he performed on air conditioning units in the normal course of his job 
created and exposed him to phosgene gas, causing him to develop pulmonary 
fibrosis.  The causes of action against defendant are based on its alleged failure to 
warn of the potential hazards of R-22 exposure.  They include negligence, strict 
                                              
2 
In July 2004, California Code of Regulations title 8, section 5194, 
subdivision (h), was amended.  Like those amendments made to subdivision (g), 
the effects of the amendment on subdivision (h) in this case are minimal. 
3  
Plaintiff has settled or dismissed all of his claims against other defendants, 
except for a claim against one refrigerant manufacturer, and one supplier of 
refrigerant.  Those parties are not involved in the present appeal. 
 
4
liability failure to warn, strict liability design defect, and breach of implied 
warranties. 
In each cause of action, plaintiff’s theory was that defendant knew that 
servicing the evaporator would create harmful phosgene gas, but defendant failed 
to provide plaintiff with an adequate warning.  (See Anderson v. Owens-Corning 
Fiberglas Corp. (1991) 53 Cal.3d 987, 1002 (Anderson).)  As the Court of Appeal 
observed, plaintiff contended that “a warning would be adequate if it informed 
users that brazing refrigerant lines can result in creation of phosgene, that phosgene 
inhalation can result in potentially fatal lung disease, that phosgene can be detected 
through its fresh-cut-grass smell, changes in flame color during brazing, or 
physical symptoms like burning eyes or shortness of breath, and that users should 
wear respiratory protection while brazing and stop brazing on detection of 
phosgene.” 
In May 2004, defendant moved for summary judgment on two grounds.  
First, the company claimed it had no duty to warn about the potential hazards of R-
22 because it did not manufacture that refrigerant; it only manufactured the 
evaporator that contained the refrigerant.  Defendant also claimed it had no duty to 
warn about the risks of R-22 exposure because it could assume that the group of 
trained professionals to which plaintiff belonged, and plaintiff himself, were aware 
of those risks.  As the Court of Appeal observed, “the undisputed facts were that 
under federal law, HVAC technicians who work on commercial equipment must be 
certified by the EPA with ‘universal’ certification, which is granted after an exam.  
They are ‘trained professionals.’  Most HVAC technicians also have some kind of 
trade or professional training.  [Plaintiff] had universal certification and had 
completed a one-year course of study in HVAC systems at ITT Technical 
 
5
Institute.”4  In September 2004, the trial court granted defendant’s motion for 
summary judgment and entered judgment in its favor on both grounds.  The Court 
of Appeal affirmed the trial court’s judgment on the sole ground that the 
sophisticated user defense applies in California.  The court held that “a 
manufacturer cannot be liable to a sophisticated user of its product for failure to 
warn of a risk, if a sophisticated user should reasonably know of that risk.”  The 
Court of Appeal held that because plaintiff’s theory was the same in all causes of 
action, i.e., product liability through the failure to warn, the sophisticated user 
defense should apply to plaintiff’s complaint in its entirety. 
The Court of Appeal next addressed whether defendant was entitled to 
summary judgment “on the theory that there was no duty to warn because the 
danger at issue was one generally known to members of the profession, one which 
[plaintiff] ‘could reasonably have been expected to know’ [citation] or . . . [that 
defendant] had ‘reason to expect’ that HVAC technicians would know of the risk.” 
The court observed that there was “undisputed evidence that HVAC 
technicians could reasonably be expected to know of the hazard of brazing 
refrigerant lines.”  Despite plaintiff’s testimony that he had read the MSDS for R-
22, but did not understand that he should avoid heating it, the Court of Appeal 
concluded that there was undisputed evidence from the relevant declarations and 
depositions of HVAC technicians that the EPA requires those professionals “to 
                                              
4 
Plaintiff has asked this court to take judicial notice of several regulations 
and regulatory interpretations of the federal Hazard Communication Standard by 
the United States Department of Labor, Occupational Safety and Health 
Administration, and has included in his request several exhibits detailing the 
problems that exposure to hazardous chemicals may cause and the labeling 
requirements for shipped containers that house the chemicals.  Defendant does not 
oppose the request, and we grant it.  (Evid. Code, §§ 452, 453.) 
 
6
understand the decomposition products of refrigerants at high temperatures.”  The 
court noted that “ ‘the study guide informed users that refrigerant in contact with 
high heat can form dangerous substances, and the Material Safety Data Sheet for 
R-22 informed technicians that the product can decompose when in contact with 
heat, releasing toxic gases.’ ”  The court affirmed the summary judgment in 
defendant’s favor.  As noted, we granted review to determine whether the 
sophisticated user defense should apply in California. 
DISCUSSION 
A.  Procedural Background; Summary Judgment 
Because plaintiff appealed from the trial court’s order granting defendant 
summary judgment, we independently examine the record in order to determine 
whether triable issues of fact exist to reinstate the action.  (Saelzler v. Advanced 
Group 400 (2001) 25 Cal.4th 763, 767.)  In this action, therefore, we must 
determine whether defendant has shown that plaintiff has not established a prima 
facie case of negligence or strict liability, “a showing that would forecast the 
inevitability of a nonsuit” in defendant’s favor.  (Id. at p. 768.)  “If so, then under 
such circumstances the trial court was well justified in awarding summary 
judgment to avoid a useless trial.”  (Ibid.)  In performing our de novo review, we 
view the evidence in the light most favorable to plaintiff as the losing party.  (Ibid.)  
In this case, we liberally construe plaintiff’s evidentiary submissions and strictly 
scrutinize defendant’s own evidence, in order to resolve any evidentiary doubts or 
ambiguities in plaintiff’s favor.  (Ibid.) 
B. Development of the Sophisticated User Defense 
 
1.  Background 
 
Generally speaking, manufacturers have a duty to warn consumers about the 
hazards inherent in their products.  (Anderson, supra, 53 Cal.3d at p. 1003.)  The 
requirement’s purpose is to inform consumers about a product’s hazards and faults 
 
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of which they are unaware, so that they can refrain from using the product 
altogether or evade the danger by careful use.  (Ibid.)  Typically, under California 
law, we hold manufacturers strictly liable for injuries caused by their failure to warn 
of dangers that were known to the scientific community at the time they 
manufactured and distributed their product.  (Ibid.; see also Carlin v. Superior 
Court (1996) 13 Cal.4th 1104, 1108 (Carlin).)  Anderson made it clear that 
“[w]hatever may be reasonable from the point of view of the manufacturer, the user 
of the product must be given the option either to refrain from using the product at all 
or to use it in such a way as to minimize the degree of danger.”  (Anderson, supra, 
53 Cal.3d at p. 1003.)  Anderson explained that the rule of strict liability imposed on 
all manufacturers for their failure to warn of known or reasonably scientifically 
knowable risks was one that we had previously required of drug manufacturers.  (Id. 
at p. 1000; Carlin, supra, 13 Cal.4th at p. 1109.)  Conversely, when a sufficient 
warning is given, “the seller may reasonably assume that it will be read and heeded; 
and a product bearing such a warning, which is safe for use if it is followed, is not in 
defective condition, nor is it unreasonably dangerous.”  (Rest.2d Torts, §  402A, 
com. j, p. 353.) 
 
The sophisticated user defense exempts manufacturers from their typical 
obligation to provide product users with warnings about the products’ potential 
hazards.  (In re Asbestos, supra, 543 F.Supp. at p. 1151.)  The defense is 
considered an exception to the manufacturer’s general duty to warn consumers, and 
therefore, in most jurisdictions, if successfully argued, acts as an affirmative 
defense to negate the manufacturer’s duty to warn.  (Ibid.) 
 
Under the sophisticated user defense, sophisticated users need not be 
warned about dangers of which they are already aware or should be aware.  (See 4 
Shearman & Redfield, Negligence (rev. ed. 1041) Manufacturers and Vendors, 
§ 656, p. 1576.)  Because these sophisticated users are charged with knowing the 
 
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particular product’s dangers, the failure to warn about those dangers is not the legal 
cause of any harm that product may cause.  (Owen, Products Liability Law (2005) 
§ 9.5, p. 599.)  The rationale supporting the defense is that “the failure to provide 
warnings about risks already known to a sophisticated purchaser usually is not a 
proximate cause of harm resulting from those risks suffered by the buyer’s 
employees or downstream purchasers.”  (Ibid.)  This is because the user’s 
knowledge of the dangers is the equivalent of prior notice.  (Billiar v. Minnesota 
Mining and Mfg. Co. (2nd Cir. 1980) 623 F.2d 240, 243 [“[N]o one needs notice of 
that which he already knows”].) 
 
As we explain further below, the sophisticated user defense evolved out of 
the Restatement Second of Torts, section 388 (section 388) and the obvious danger 
rule, an accepted principle and defense in California.  (Stevens v. Parke, Davis & 
Co. (1973) 9 Cal.3d 51, 64; Bojorquez v. House of Toys, Inc. (1976) 62 Cal.App.3d 
930, 933-934 (Bojorquez).)  In addition, as we explain, the defense applies equally 
to strict liability and negligent failure to warn cases.  The duty to warn is measured 
by what is generally known or should have been known to the class of 
sophisticated users, rather than by the individual plaintiff’s subjective knowledge.  
(See, e.g., Humble Sand & Gravel, Inc. v. Gomez (Tex. 2004) 146 S.W.3d 170, 
183.) 
 
 
2.  Section 388 and the Obvious Danger Rule 
 
Section 388 provides that a supplier of goods is liable for physical harm the 
goods cause if the supplier knows, or should know, the items are likely to be 
dangerous, fails to reasonably warn of the danger, and “has no reason to believe 
that those for whose use the chattel is supplied will realize its dangerous 
condition.”  Comment k to section 388, subdivision (b), is entitled “When warning 
of defects unnecessary,” and it emphasizes this point.  It declares that although the 
condition may be one that only specialists would perceive, the supplier is only 
 
9
required to inform the users of the risk if the manufacturer has “no reason to 
believe that those who use it will have such special experience as will enable them 
to perceive the danger[.]”  (§ 388, subd. (b), com. k, p. 307.) 
 
Courts have interpreted section 388, subdivision (b), to mean that if the 
manufacturer reasonably believes the user will know or should know about a given 
product’s risk, the manufacturer need not warn that user of that risk.  (Martinez v. 
Dixie Carriers, Inc. (5th Cir. 1976) 529 F.2d 457, 464-465; Lockett v. General 
Electric Company (E.D.Pa. 1974) 376 F.Supp. 1201, 1208-1209, affd. (3d Cir. 
1975) 511 F.2d 1394; Bryant v. Hercules Incorporated (W.D.Ky. 1970) 325 
F.Supp. 241, 247.)   This is “especially [true] when the user is a professional who 
should be aware of the characteristics of the product.”  (Strong v. E. I. Du Pont de 
Nemours Co., Inc. (8th Cir. 1981) 667 F.2d 682, 687.) 
 
Other jurisdictions that have adopted the sophisticated user defense have 
cited section 388 and the obvious danger rule as a basis for doing so.  (E.g., Akin v. 
Ashland Chemical (10th Cir. 1998) 156 F.3d 1030, 1037 [no need to warn a 
knowledgeable purchaser like the United States Air Force about the dangers of 
low-level chemical exposure]; Strong v. E. I. Du Pont de Nemours Co., Inc., supra, 
667 F.2d at pp. 686-687 [natural gas pipe manufacturer had no duty to warn a 
natural gas utility, or the utility’s employee, of well known gas line dangers].)  
Other courts have employed the same principle to justify the sophisticated user 
defense without specifically citing the Restatement Second of Torts.  (E.g., Antcliff 
v. State Employees Credit Union (Mich. 1982) 327 N.W.2d 814, 818-819, 821 
[scaffolding manufacturer had no duty to give information and instruction about 
safe rigging procedure to a professional painter experienced in rigging procedure].)  
While this court has not expressly adopted a sophisticated user defense, it has 
adopted  section 388 as law in California.  (See Stevens v. Parke, Davis & Co., 
supra, 9 Cal.3d at p. 64.) 
 
10
 
California law also recognizes the obvious danger rule, which provides that 
there is no need to warn of known risks under either a negligence or strict liability 
theory.  (Bojorquez, supra, 62 Cal.App.3d at pp. 933-934; Holmes v. J. C. Penney 
Co. (1982) 133 Cal.App.3d 216, 220.)  In Bojorquez, a child bought a slingshot 
from a 7-Eleven store and used it to shoot a projectile at the plaintiff, injuring one 
of her eyes.  (Bojorquez, supra, 62 Cal.App.3d at p. 932.)  The plaintiff sued the 
slingshot’s retailer and wholesaler, claiming several causes of action, including 
strict liability for failing to warn about a slingshot’s dangers.  (Ibid.)  The trial 
court dismissed her claim, and the Court of Appeal affirmed the judgment, 
observing that “the seller does not need to add a warning when ‘the danger, or 
potentiality of danger[,] is generally known and recognized.’  . . . There is no need 
to include a warning; the product is not defective because it lacked a warning; there 
is no cause of action in strict liability.”  (Id. at pp. 933-934, quoting Restatement 2d 
Torts, § 402A, com. j.)  Similarly, Holmes v. J. C. Penney Co., supra, 133 
Cal.App.3d at page 220, relying on Bojorquez, held that the dangers and potential 
harms associated with firing a pellet gun were obvious and did not require the 
seller to warn about them.  (See also Plenger v. Alza Corp. (1992) 11 Cal.App.4th 
349, 362 [manufacturer of intrauterine device not strictly liable to patient who died 
after doctors implanted manufacturer’s product:  “We are aware of no authority 
which requires a manufacturer to warn of a risk which is readily known and 
apparent to the consumer, in this case the physician.  Further, if the risk . . . is 
universally known in the medical profession, the failure to warn the physician of 
that risk cannot be the legal cause of the decedent’s death”].) 
 
Although the Court of Appeal was aware that “no California court has 
squarely adopted the [sophisticated user] doctrine,” the court observed that “it is a 
natural outgrowth of the rule that there is no duty to warn of known risks or 
obvious dangers.”  As the Court of Appeal reasoned, the sophisticated user defense 
 
11
simply recognizes the exception to the principle that consumers generally lack 
knowledge about certain products, for example, heavy industrial equipment, and 
hence the dangers associated with them are not obvious.  For those individuals or 
members of professions who do know or should know about the product’s potential 
dangers, that is, sophisticated users, the dangers should be obvious, and the defense 
should apply.  Just as a manufacturer need not warn ordinary consumers about 
generally known dangers, a manufacturer need not warn members of a trade or 
profession (sophisticated users) about dangers generally known to that trade or 
profession. 
 
 
3.  Fierro v. International Harvester Co. 
 
One California court has, in dictum, addressed the sophisticated user 
defense in the strict liability context, and the court’s decision has been the focus of 
federal jurisprudence discussed further below.  (Fierro v. International Harvester 
Co. (1982) 127 Cal.App.3d 862 (Fierro).)  The plaintiff, Fierro, sued International 
Harvester Company (International), because it manufactured the truck her husband 
was driving when he crashed and died.  (Id. at p. 865.)  International manufactured 
skeleton trucks that came with only an engine, cab and chassis, which allowed 
purchasers to complete or add to the truck as they saw fit.  (Ibid.)  Luer Packaging 
Company (Luer) purchased one of these trucks from International and installed a 
refrigeration unit on the chassis.  (Ibid.)  Five years later, the plaintiff’s husband 
was driving the truck in the course and scope of his job with Luer.  The truck 
overturned after blowing a tire, crashed, skidded for a distance, spilled fuel, and 
caught fire.  (Ibid.) 
 
The plaintiff and Luer’s worker’s compensation insurance carrier brought a 
wrongful death action seeking to impose liability on International for negligence 
and manufacturer’s strict liability.  (Fierro, supra, 127 Cal.App.3d at p. 865.)  The 
evidence at trial focused on “the location of the fuel tank and filler necks and their 
 
12
exposure to damage when the truck struck the guard rail and turned over.”  (Ibid.)  
During trial, the plaintiff alleged that International had to warn Luer that attaching 
power cables from the refrigerator unit to the truck’s battery could create a fire 
hazard.  (Id. at p. 866.)  Even though these were not dangers an average consumer 
would perceive, the trial court refused to instruct the jury on the issue of failure to 
warn.  (Ibid.)  The Court of Appeal affirmed the trial court’s judgment after 
concluding that the court was justified in not instructing the jury on the failure to 
warn because the plaintiff had not properly raised that issue at trial.  (Ibid.) 
 
In dictum, the Court of Appeal explained that International, as the defendant 
manufacturer,  need not warn the purchaser Luer because “[a] sophisticated 
organization like Luer does not have to be told that gasoline is volatile and that 
sparks from an electrical connection or friction can cause ignition.”  (Fierro, supra, 
127 Cal.App.3d at p. 866.)  The court observed that “[t]here was no evidence that 
any feature of the skeleton unit was unique or contained any component or 
capability which was known to International and which was not known to or 
readily observable by Luer.  The fuel tanks and the filler spouts were patently 
exposed, and they were obviously designed to hold gasoline.  The properties and 
propensities of that volatile liquid are a matter of common knowledge.  Nor did 
Luer need to be advised of the necessity to cover and protect the exposed fuel tanks 
before operating the unit under circumstances which could subject them to 
damage.”  (Ibid.)  In other words, the lack of a warning “to Luer did not 
substantially or unreasonably increase any danger that may have existed in using 
the [truck].”  (Ibid.)  The Court of Appeal impliedly adopted the sophisticated user 
defense in rationalizing its affirmance of the trial court’s judgment. 
 
 
4.  Federal Decisions 
 
The federal courts took notice of Fierro and predicted that this court would 
eventually adopt the sophisticated user defense.  In an important products liability 
 
13
action filed in the Northern District of California, the plaintiffs “were insulators 
and shipyard workers employed by the United States Navy during varying periods.  
In the course of their employment with the Navy, plaintiffs were allegedly exposed 
to asbestos products manufactured by defendants.  Plaintiffs claim[ed] that 
defendants’ asbestos products caused injury to them.”  (In re Asbestos, supra, 543 
F.Supp. at p. 1150.)  The defendants claimed “that the Navy was negligent in 
failing to provide plaintiffs with a safe work place and that this negligence 
constituted a superseding cause sufficient to relieve defendants of liability.”  (Ibid.)  
The court agreed that the sophisticated user defense applied to strict liability claims 
and refused to grant the plaintiffs’ motion to strike the defense.  (Ibid.)  The court 
believed the highest California court would permit the defense.  The federal court 
recognized, however, that under California law the plaintiffs could undercut the 
application of the sophisticated user defense by demonstrating that the defendants 
might have foreseen the Navy’s alleged negligence, and so it should not absolve 
them of liability.  (Id. at pp. 1150-1151.)5 
 
In re Asbestos, supra, 543 F.Supp. at page 1151, pointed out that the 
defendants also asserted “that the Navy was a ‘sophisticated user’ of asbestos 
products — that is, that the Navy, as an employer, was as aware of the dangers of 
asbestos as were defendants and that the Navy nonetheless misused the products, 
thereby absolving the defendants of liability for failure to warn the Navy’s 
employees of the products’ dangers.”  Various federal courts that have applied state 
                                              
5 
The federal court’s prediction that this court would adopt the sophisticated 
user defense on the condition that a plaintiff could negate it by showing that the 
sophisticated user’s misuse of the product was foreseeable is not at issue here, and 
we do not address it at this time.  (See In re Asbestos, supra, 543 F.Supp. at p. 
1151.) 
 
 
14
law under diversity jurisdiction have allowed the sophisticated user defense.  (See, 
e.g., In re Air Crash Disaster, supra, 86 F.3d at pp. 521-522 [applying 
sophisticated user defense in finding no negligence for manufacturer’s failure to 
warn of danger in aircraft warning system]; Bradco Oil & Gas Co. v. Youngstown 
Sheet & Tube Co. (5th Cir. 1976) 532 F.2d 501, cert. den. (1977) 429 U.S. 1095 
[97 S.Ct. 1111, 51 L.Ed. 542] [sophisticated user defense applied in a strict liability 
case]; In re Asbestos, supra, 543 F.Supp. at p. 1151.)  Although federal circuit and 
district court decisions interpreting state law are not binding on our court, we find 
their reasoning persuasive in adopting the sophisticated user defense in our 
jurisdiction.  (See People v. Bradley (1969) 1 Cal.3d 80, 86.) 
 
 
5.  The Selma Decision 
 
Plaintiff asserts that we should adopt the reasoning of Selma Pressure 
Treating Co. v. Osmose Wood Preserving Co. (1990) 221 Cal.App.3d 1601, which  
rejected the sophisticated user defense.  But a close reading of Selma indicates that 
the court did not reject the defense at all.  The issue in Selma was whether a 
manufacturer had to warn the general public of the risks of damage its chemicals 
caused that the ordinary user could not reasonably be expected to know.  Selma 
acknowledged the sophisticated user defense through its pronouncement that the 
existence of unknown dangers gives rise to the duty to warn.  (Id. at p. 1623.)  
Selma recognizes that a defendant may introduce evidence demonstrating that “a 
user has sufficient expertise to be charged with the knowledge of risks associated 
with a particular product.”  (Ibid.)  Selma’s holding, therefore, is consistent with 
the sophisticated user defense and the other case law discussed thus far.  Nothing in 
Selma’s reasoning persuades us not to adopt the sophisticated user defense, and to 
the extent that it might cause confusion, we would disapprove of its reasoning. 
 
15
 
C.  Public Policy 
 
Not all warnings, however, promote user safety.  Requiring manufacturers 
to warn their products’ users in all instances would place an onerous burden on 
them and would “ ‘invite mass consumer disregard and ultimate contempt for the 
warning process.’ ” (Finn v. G. D. Searle & Co. (1984) 35 Cal.3d. 691, 701, 
quoting Twerski et al., The Use and Abuse of Warnings in Products Liability — 
Design Defect Litigation Comes of Age (1976) 61 Cornell L. Rev. 495, 521]; see 
also Rest.3d Torts, Products Liability, § 2, com. j, p. 31 [“[R]equiring warnings of 
obvious or generally known risks could reduce the efficacy of warnings 
generally”].)  The sophisticated user defense fits into this understanding of the role 
of warnings; it helps ensure that warnings will be heeded. 
 
In addition, numerous generally safe products exist that can become 
hazardous when the proper precautions are not followed.  Although manufacturers  
are responsible for products that contain dangers of which the public is unaware, 
they are not insurers, even under strict liability, for the mistakes or carelessness of 
consumers who should know of the dangers involved.  (Anderson, supra, 53 Cal.3d 
at p. 994.)  Accordingly, we adopt the defense in California.  We now examine the 
defense’s exact contours. 
 
D.  How the Defense Operates in California 
 
 
1.  A “Should Have Known” Standard 
A manufacturer is not liable to a sophisticated user of its product for failure 
to warn of a risk, harm, or danger, if the sophisticated user knew or should have 
known of that risk, harm, or danger.  It would be nearly impossible for a 
manufacturer to predict or determine whether a given user or member of the 
sophisticated group actually has knowledge of the dangers because of the infinite 
number of user idiosyncrasies.  For example, given users may have misread their 
training manuals, failed to study the information in those manuals, or simply 
 
16
forgotten what they were taught.  However, individuals who represent that they are 
trained or are members of a sophisticated group of users are saying to the world 
that they possess the level of knowledge and skill associated with that class.  If they 
do not actually possess that knowledge and skill, that fact should not give rise to 
liability on the part of the manufacturer. 
Under the “should have known” standard there will be some users who were 
actually unaware of the dangers.  However, the same could be said of the currently 
accepted obvious danger rule; obvious dangers are obvious to most, but are not 
obvious to absolutely everyone.  The obvious danger rule is an objective test, and 
the courts do not inquire into the user’s subjective knowledge in such a case.  In 
other words, even if a user was truly unaware of a product’s hazards, that fact is 
irrelevant if the danger was objectively obvious.  (3 American Law of Products 
Liability (3d ed. 1993) Warnings, § 32.66, p. 113-114; Bowersfield v. Suzuki Motor 
Corp. (E.D.Pa. 2000) 111 F.Supp.2d 612, 622; see Solen v. Singer (1949) 89 
Cal.App.2d 708, 714 [there is no obligation “ ‘to give warning of an obvious 
danger or one which should have been perceived by the invitee’ ” (italics added)]; 
see also Simmons v. Rhodes & Jamieson, Ltd. (1956) 46 Cal.2d 190,194.)  Thus, 
under the sophisticated user defense, the inquiry focuses on whether the plaintiff 
knew, or should have known, of the particular risk of harm from the product giving 
rise to the injury. 
 
2.  Applicability to Negligence and Strict Liability Causes of Action 
 
As noted above, although California law recognizes the differences between 
negligence and strict liability causes of action (Anderson, supra, 53 Cal. 3d at p. 
987), the sophisticated user defense is applicable to both.  As amicus curiae 
Chamber of Commerce of the United States of America et al. observe, our 
Anderson holding recognizes there is little functional difference between the two 
theories in the failure to warn context.  (See, e.g., Cupp & Polage, The Rhetoric of 
 
17
Strict Products Liability Versus Negligence: An Empirical Analysis (2002) 77 
N.Y.U. L.Rev. 874 [noting there is little substantive distinction between negligence 
and strict liability causes of action in the failure to warn context].) 
 
In addition, as noted, Fierro, without discussing the issue in dictum, applied 
the sophisticated user defense to a strict liability cause of action.  (Fierro, supra, 
127 Cal.App.3d at pp. 865, 866.)  Likewise, California courts have applied the 
obvious danger rule to strict liability causes of action.  (See Bojorquez, supra, 62 
Cal.App.3d at pp. 933-934; Holmes v. J. C. Penney Co., supra, 133 Cal.App.3d at 
p. 220.) 
 
Plaintiff asserts that applying the “should have known” prong of the 
sophisticated user defense incorrectly converts his strict liability cause of action 
into a negligence cause of action.  He claims that if we adopt the sophisticated user 
defense, we should limit its applicability to strict liability failure to warn claims in 
which a plaintiff had actual knowledge of the danger in question.  Anything less, 
plaintiff claims, would convert his strict liability failure to warn cause of action 
“into nothing more than a cause of action for negligence.”  We disagree. 
 
As plaintiff observes, some states recognize the sophisticated user defense 
in negligence actions, but reject it in strict products liability cases.  (See, e.g., 
Russo v. Abex Corp. (E.D.Mich. 1987) 670 F.Supp. 206, 207 [sophisticated user 
defense used in negligence cases does not exist under strict liability principles 
because “seller is duty-bound to warn all foreseeable users,” even sophisticated 
ones]; accord, Menna v. Johns-Manville Corp.  (D.N.J. 1984) 585 F.Supp. 1178, 
1184 [sophisticated user defense applicable to negligence claims only; duty to warn 
cannot depend on plaintiff’s knowledge level or sophistication].)  As defendant 
observes, however, the use of a “should have known” standard does not conflict 
with principles of strict liability.  Strict liability requires “ ‘a plaintiff to prove only 
that the defendant did not adequately warn of a particular risk . . . .’ ”  (Carlin, 
 
18
supra, 13 Cal.4th at p. 1112.)  In the context of sophisticated user defense, because 
the intended users are deemed to know of the risks, manufacturers have no 
obligation to warn, and providing no warning is appropriate.  The focus of the 
defense, therefore, is whether the danger in question was so generally known 
within the trade or profession that a manufacturer should not have been expected to 
provide a warning specific to the group to which plaintiff belonged.  Consequently, 
there is no reason why the sophisticated user defense should not be as available 
against strict liability causes of action as it is for negligence causes of action.  In 
both instances, the sophisticated user’s knowledge eliminates the manufacturer’s 
need for a warning. 
 
This approach is consistent with the Restatement Second of Torts, section 
402A, which addresses strict liability.  Comment j instructs that even in cases of 
strict liability “a seller is not required to warn . . . when the danger, or potentiality 
for danger, is generally known and recognized.”  (Restatement 2d Torts, supra, 
§ 402A, com. j, p. 353.)  In addition, even if the “should have known” standard is 
considered more closely aligned with a negligence concept, we have repeatedly 
held that strict liability products liability law in California may incorporate 
negligence concepts without undermining the principles fundamental to a strict 
liability claim.  (See, e.g., Anderson, supra, 53 Cal.3d at pp. 1002-1003 [requiring 
manufacturers to warn of dangers that are known or reasonably knowable]; Daly v. 
General Motors Corp. (1978) 20 Cal.3d 725, 734 [holding that principles of 
comparative fault apply in strict products liability actions]; Barker v. Lull 
Engineering Co. (1978) 20 Cal.3d 413, 433 [adopting risk-benefit test for design 
defect claims and rejecting claim that test improperly introduces an element that 
“ ‘rings of negligence’ ”].) 
 
In Anderson, this court stated that “the claim that a particular component 
‘rings of’ or ‘sounds in’ negligence has not precluded its acceptance in the context 
 
19
of strict liability. . . .  [¶]  . . .  [¶] . . . [T]he strict liability defense has incorporated 
some well-settled rules from the law of negligence and has survived judicial 
challenges asserting that such incorporation violates fundamental principles of the 
defense.”  (Anderson, supra, 53 Cal.3d at pp. 1001-1004.)  Anderson agreed that 
failure to warn claims involve some consideration of the defendant’s conduct and 
do not necessarily focus exclusively on the product’s condition.  The court 
recognized that “[i]t may also be true that the ‘warning defect’ theory is ‘rooted in 
negligence’ to a greater extent than are the manufacturing — or design-defect 
theories.  The ‘warning defect’ relates to a failure extraneous to the product itself.  
Thus, while a manufacturing or design defect can be evaluated without reference to 
the conduct of the manufacturer [citation], the giving of a warning cannot.  The 
latter necessarily requires the communicating of something to someone.”  (Id. at p. 
1002.) 
 
 
3.  Determining User Sophistication 
 
The relevant time for determining user sophistication for purposes of this 
exception to a manufacturer’s duty to warn is when the sophisticated user is injured 
and knew or should have known of the risk.  (See Crook v. Kaneb Pipe Line 
Operating Partnership (8th Cir. 2000) 231 F.3d 1098, 1102.)  As amicus curiae 
Product Liability Advisory Counsel observe, the Court of Appeal “correctly 
understood the defense to eliminate any duty to warn when the expected user 
population is generally aware of the risk at issue, and correctly rejected the 
argument that a manufacturer’s duty to warn should turn on the individual 
plaintiff’s actual understanding of the risk.  Legal duties must be based on 
objective general predictions of the anticipated user population’s knowledge, not 
case-by-case hindsight examinations of the particular plaintiff’s subjective state of 
mind.”  As the Court of Appeal pointed out, “[t]he sophisticated user defense will 
always be employed when a sophisticated user should have, but did not, know of 
 
20
the risk.  Otherwise, the issue would be actual knowledge and causation.”  
Therefore, the sophisticated user’s knowledge of the risk is measured from the time 
of the plaintiff’s injury, rather than from the date the product was manufactured.  
The timeline focuses on the general population of sophisticated users and conforms 
to the defense’s purpose to eliminate any duty to warn when the expected user 
population is generally aware of the risk at issue. 
DISPOSITION 
For the reasons explained above, we conclude that the sophisticated user 
defense applies in California.  Like the Court of Appeal, we also conclude that the 
defense should apply in this case to defeat all causes of action for defendant’s 
alleged failure to warn.  As the Court of Appeal observed, defendant presented 
undisputed evidence that HVAC technicians could reasonably be expected to know 
of the hazard of brazing refrigerant lines.  Plaintiff’s expert testified that HVAC 
technicians knew or should have known of the risk of phosgene at the time 
defendant manufactured the product in 1965.  Defendant’s expert testified that 
throughout his 28 years as an HVAC technician, it was “widely known among 
HVAC technicians” that when R-22 is heated it can decompose into toxic by-
products that include phosgene.  Thus, the danger created by exposing refrigerant 
to high heat and flame was well known within the community of HVAC 
technicians to which plaintiff belonged. 
Plaintiff’s claim that he had read the MSDS for R-22 but did not understand 
that he should avoid heating R-22 is also without merit.  The expert testimony at 
trial showed that the EPA requires HVAC professionals “to understand the 
decomposition products of refrigerants at high temperatures.”  In addition, 
plaintiff’s excuse that he had never heard of phosgene gas and that when he 
smelled the fresh-cut-grass odor he did not stop or take any precaution, also does 
not support his claim.  As noted above, the study guide informed HVAC 
 
21
technicians that R-22 can form dangerous substances when in contact with high 
heat, and the MSDS for R-22 informed technicians that the product can decompose 
and release toxic gases when in contact with heat.  The evidence is clear that 
HVAC technicians knew or should have known of the dangers of R-22 heat 
exposure. 
For all these reasons, we conclude that there is no triable issue of fact 
regarding applicability of the sophisticated user defense in this case.  We therefore 
affirm the Court of Appeal’s judgment. 
 
 
 
 
 
 
 
 
CHIN, J. 
WE CONCUR: 
 
GEORGE, C.J. 
KENNARD, J. 
BAXTER, J. 
WERDEGAR, J. 
MORENO, J. 
LEVY, J.P.T.* 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
________________________ 
* 
Associate Justice, Court of Appeal, Fifth Appellate District, assigned by the 
Chief Justice pursuant to article VI, section 6 of the California Constitution.
 
 
See next page for addresses and telephone numbers for counsel who argued in Supreme Court. 
 
Name of Opinion Johnson v. American Standard, Inc. 
__________________________________________________________________________________ 
 
Unpublished Opinion 
Original Appeal 
Original Proceeding 
Review Granted XXX 133 Cal.App.4th 496 
Rehearing Granted 
 
__________________________________________________________________________________ 
 
Opinion No. S139184 
Date Filed: April 3, 2008 
__________________________________________________________________________________ 
 
Court: Superior 
County: Los Angeles 
Judge: Susan Bryant-Deason 
 
__________________________________________________________________________________ 
 
Attorneys for Appellant: 
 
Metzger Law Group, Raphael Metzger, Gregory A. Coolidge and Peter F. Klein for Plaintiff and Appellant. 
 
Steven G. Ingram and Sharon J. Arkin for Consumer Attorneys for California as Amicus Curiae on behalf of 
Plaintiff and Appellant. 
 
 
 
__________________________________________________________________________________ 
 
Attorneys for Respondent: 
 
Munger, Tolles & Olson, Jeffrey L. Bleich, Kathleen M. McDowell, Paul J. Watford, Blanca Fromm Young 
and Aimee Feinberg for Defendant and Respondent. 
 
Hugh F. Young, Jr.; Martin, Bischoff, Templeton, Langlset & Hoffman, Jonathan M. Hoffman; Drinker 
Biddle & Reath and Alan Lazarus for Product Liability Advisory Council, Inc., as Amicus Curiae on behalf 
of Defendant and Respondent. 
 
Horvitz & Levy, David M. Axelrad, Mary-Christine Sungaila; National Chamber Litigation Center, Inc., 
and Robin S. Conrad for Chamber of Commerce of the United States Of America, American Chemistry 
Council, American International Companies, ExxonMobil Corporation, The Farmers Insurance Group of 
Companies and Honeywell International, Inc., as Amici Curiae on behalf of Defendant and Respondent. 
 
Duane Morris, Robert L. Byer, Paul J. Killion and Kathryn K. Schutz for FLSMIDTH, Inc., as Amicus 
Curiae on behalf of Defendant and Respondent. 
 
 
 
 
 
 
 
 
Counsel who argued in Supreme Court (not intended for publication with opinion): 
 
Gregory A. Coolidge 
Metzger Law Group 
401 E. Ocean Boulevard, Suite 800 
Long Beach, CA  90802 
(562) 437-4499 
 
Sharon J. Arkin 
Consumer Attorneys of California 
770 L Street, Suite 1200 
Sacramento, CA  95814 
(916) 442-6902 
 
Jeffrey L. Bleich 
Munger, Tolles & Olson 
560 Mission Street, 27th Floor 
San Francisco, CA  94105 
(415) 512-4000