HP is aware of the reliability risk factors related to the use of red phosphorus as a flame retardant and is taking steps to mitigate this risk.  Two key HP standards, HP General Semiconductor Specification/EL-MF862-05,  and HP General Interconnect Specification/EL-MF862-04, were updated in 2014, to ban the use of red phosphorus as a flame retardant in semiconductor packages and connectors.


The specific personal systems products listed were launched before these standards were updated and could contain red phosphorus.  We don't know that they do, but we also can't state that they did not use red phosphorus.