diff --git a/R/constructNWISURL.r b/R/constructNWISURL.r
index eb58d0c6ffe80058b650ff7f6686b9d720f5f5be..11440d146aa2c8d12fc90e50d88538240a678bea 100644
--- a/R/constructNWISURL.r
+++ b/R/constructNWISURL.r
@@ -48,7 +48,7 @@ constructNWISURL <- function(siteNumber,parameterCd="00060",startDate="",endDate
 
   service <- match.arg(service, c("dv","uv","iv","qw","gwlevels","rating","peak","meas"))
   
-  data(parameterCdFile)
+  data("parameterCdFile")
   
   if(any(!is.na(parameterCd))){
     pcodeCheck <- all(nchar(parameterCd) == 5) & all(!is.na(suppressWarnings(as.numeric(parameterCd))))
diff --git a/R/readNWISpCode.r b/R/readNWISpCode.r
index 95b9a66ef5052a9220c3ceeb1d069f3c88a4cd20..01e4dee75e5b31f7c4779a8fca0c3cbeb21d4b33 100644
--- a/R/readNWISpCode.r
+++ b/R/readNWISpCode.r
@@ -24,6 +24,8 @@ readNWISpCode <- function(parameterCd){
  
   pcodeCheck <- all(nchar(parameterCd) == 5) & all(!is.na(suppressWarnings(as.numeric(parameterCd))))
   
+  data("parameterCdFile")
+  
   if(!pcodeCheck){
     goodIndex <- which(parameterCd %in% parameterCdFile$parameter_cd)
     if(length(goodIndex) > 0){
@@ -35,8 +37,6 @@ readNWISpCode <- function(parameterCd){
     parameterCd <- parameterCd[goodIndex]
   }
   
-  data(parameterCdFile)
-  
   parameterData <- parameterCdFile[parameterCdFile$parameter_cd %in% parameterCd,]
 
   if(nrow(parameterData) != length(parameterCd)){
diff --git a/R/whatNWISData.r b/R/whatNWISData.r
index 1d2ed461b426b8af800ed924da8b0403ad4418bd..b795d3ce995f6fb6a4839e21298c03e63990f26c 100644
--- a/R/whatNWISData.r
+++ b/R/whatNWISData.r
@@ -71,6 +71,9 @@ whatNWISdata <- function(siteNumbers,service="all",parameterCd="all",statCd="all
   if(!("all" %in% service)){
     service <- match.arg(service, c("dv","uv","qw","ad","id","pk","sv","gw","aw","all","ad","iv","rt"), several.ok = TRUE)
   }
+
+  
+  data("parameterCdFile")
   
   if(!("all" %in% parameterCd)){
     parameterCdCheck <- all(nchar(parameterCd) == 5) & all(!is.na(suppressWarnings(as.numeric(parameterCd))))
@@ -96,8 +99,6 @@ whatNWISdata <- function(siteNumbers,service="all",parameterCd="all",statCd="all
   
   parameterCds <- unique(SiteFile$parm_cd)
   
-  data(parameterCdFile)
-  
   parameterCdINFO <- parameterCdFile[parameterCdFile$parameter_cd %in% parameterCds,]
   SiteFile <- merge(SiteFile,parameterCdINFO,by.x="parm_cd" ,by.y="parameter_cd",all=TRUE)